In July 1988 an Iran Air civilian passenger airliner was shot down by a surface-to-air missile fired by the US cruiser Vincennes. All 290 passengers, including many children, were killed. The plane was still in Iranian airspace on a scheduled international flight en route from Tehran to Dubai in an approved commercial air corridor. The Vincennes had entered Iranian waters without permission.

At the time, the Iranian government labelled the attack a crime and an atrocity. The US government acknowledged that the Vincennes had incorrectly identified the plane as an Iranian fighter jet but defended the action, stating this was a wartime incident. In other words, ''collateral damage''.

The UN Security Council declined to condemn the US action, instead noting its profound regret and pressing for an end to the Iran-Iraq war.

Is it not entirely feasible that the Ukrainian separatists made the same kind of awful mistake? Especially since, just days before the MH17 disaster, the Ukrainian air force had bombed villagers in the area where the plane was shot down.

Tony Abbott has been most precipitous in branding the MH17 disaster a ''heinous crime'', implying that Ukrainian separatists had a deliberate intention to kill innocent civilians in the air.

Mr Abbott cannot possibly have sufficient evidence to justify this statement but, in his usual fashion, has simply ''let fly''. In doing so, he may have lessened the willingness of those on the ground to acknowledge their dreadful error or facilitate an independent investigation.

Martha Kinsman, Kaleen

The destruction of MH17 is a tragedy, no doubt about that. Who did it? No one knows for certain.

As I peruse the internet, I see what appears to be a rush to judgment in the West, arrived at well before any sort of investigation has been carried out.

Suspicions are not enough; trial by media, simply wrong. We need to seek justice fairly and impartially. Mr Abbott leapt into the arena far too early with his bold assertions of guilt.

Both the West and Russia have been interfering in Ukrainian affairs for years; both have been supporting their factions in the conflict. It is not a simple, one-sided affair but a tangled and difficult situation.

We would do well to hold our peace until we can speak from knowledge and not from preconceptions.

Walter Steensby, Hawker

While the US has chosen to use the Malaysia Airlines disaster as a political tool against Russia, perhaps the real question is why the carrier put its crew and passengers at risk by flying over a known area of armed conflict when other airlines chose not to?

P.J. Carthy, McKellar

For once I agree with every word that Barnaby Joyce says in an opinion piece (Canberra Times, July 19).

As someone who has spent a lot of time over the years on sheep properties and in woolsheds, I know that occasionally sheep can be treated roughly during sheering, but the footage from PETA is quite extraordinary and horrendous.

Any property owner who saw such behaviour would immediately dismiss the shearing team, and that team would be unlikely to get another job in the district. Sheep are valuable assets and graziers always work in their interests.

Assuming the filming was not a put-up job, many questions arise about the ''animal rights'' group's behaviour, as pointed out by Senator Joyce. The main questions were outlined by the RSPCA's Steve Coleman: why did PETA not immediately go to the proper authorities to have the perpetrators punished? Why did they wait for two years before doing anything? And why did they then produce virtually useless, if spectacular, evidence? Could they not be regarded legally as accessories after the fact?

With vegetarians among its members, PETA's aim seems to be to drive out of business those who grow domestic animals for their livelihood - this in a world where most people want to eat some high-protein animal food.

It amazes me that their most high-profile activities in recent years have concerned free-range cattle in northern Australia and sheep in New South Wales. These animals lead as good an existence as any commercial animals, but if PETA had its way, they would have no existence at all.

To hear a glib comment from a PETA spokeswoman that there is no such thing as humanely produced wool and that we should all buy synthetics typifies this strange group. Wool is a lovely product that has been used for clothing for thousands of years and, unlike synthetic clothing, is not produced from non-renewable fossil fuels. The production of wool and meat by hard-working Australians is to be applauded, not condemned.

PETA has highlighted some real animal cruelty, but it is unscrupulous in not going through the normal channels to deal with the problem when it sees it, instead setting out to destroy ethical industries, and hence those employed in them.

On balance, PETA appears to be a self-obsessed organisation with no understanding of the real world. It deserves no support in Australia.

Neville Exon, Chapman

I wish to thank Rodney from Bruce (a generous mechanic in spirit and deed) who helped me with my car at the national arboretum on Sunday.

It was late afternoon when my plans to drive home after spending time in the village centre quickly went awry after the noise coming from under my car suggested something serious.

On hearing the awful screeching and seeing me parked by the side of the road scratching my head, Rodney offered his help and promptly got down in the gravel (a small piece of which was ultimately the reason behind my troubles). He diagnosed the issue, jacked up the car, and had the wheel off before I could say: ''Are you sure?''

Rodney's generosity in offering his time, effort and expertise to a stranger in a spot of bother (while his wife and daughter waited patiently in the fading light and cooling air as though this was the norm for their husband/dad) reminded me that Australians are extraordinarily decent people when others need a helping hand. Thanks again stranger.

Julie Hope, Nicholls

As the debate continues for the Commonwealth to hand back to the ACT government the national functions now undertaken by the NCA, Brett Odgers (Letters, July 21) raises the possibility of risks to the integrity and prospects of our national capital.

These concerns are indeed real. I suggest that as national functions are integrated into those of the ACT, it is timely to revisit all territory planning functions to establish a more relevant and innovative regime.

The ACTPLA has a historic culture perceived by many residents as being hostile to delivering aesthetically appealing architectural and landscape design. The authority is seen to deliver greenwash instead of addressing the realities of climate change and sustainability.

Just how many more cheaply rendered apartments can this city cram into old and new suburbs?

The former chief minister restructured the government departments to change the ACTPLA and its culture. Serious bureaucratic moves were made, but unfortunately the authority still remains and performs as before.

Meanwhile the NCA is soon to have its own Commonwealth-employed parking inspectors to function alongside those employed by the ACT. This will be yet another duplication of government functions in Canberra.

The integration of the national roles with those of the ACT government is overdue and could be a win-win for all by delivering a new sophisticated agency to oversee local and national planning and design responsibilities across Canberra.

Paul Costigan, Dickson

Like Brian Hatch (Letters, July 19), J. McKerrall is clutching at soggy straws (Letters, July 21).

Mr Hatch extrapolates temperature data (some of dubious reliability) from one town in south-eastern NSW to the whole of Australia.

Mr McKerrall ups the ante to a global scale, claiming the Japanese-European IBUKI/GOSAT data shows Australia is a net absorber (''sequester'') of carbon dioxide.

Unfortunately, Mr McKerrall has either not conducted his research well or, more likely, has seized on the data that conforms to his view.

The IBUKI/GOSAT figures are highly sensitive to seasonal variations. For example, in June and July 2009, the data showed atmospheric CO2 levels over Australia were relatively low, while the highest levels were over North Africa (notably the Sahara Desert), the Arabian Peninsula and the drier parts of Pakistan, India and southern Afghanistan.

In July 2009, the lowest readings were recorded over the forests of northern Russia (notably Siberia).

In November 2009, the highest readings were again over the Sahara etc, and the lowest over the still-green Siberian forests, northern Canada and Alaska.

The IBUKI/GOSAT satellites are recording seasonal variations in atmospheric CO2 that are largely due to vegetation.

Human-produced CO2 is part of the background, as is clearly shown by the contrast between the Sahara and Siberia. Mr McKerrall is indeed clutching at straws, and even they are illusory.

Douglas Mackenzie, Deakin

Both Richard Moss and Greg Simmons (Letters, July 17) are in error about the dismissal. The governor-general did not choose the day to act - the choice was Gough Whitlam's.

If Mr Whitlam had wanted more time to negotiate with the alleged waverers in the Coalition he could have had it, but he chose not to wait. Had he wanted to face the electorate as prime minister he could have done so, but he refused to take the opportunity. Instead, he chose that day to call on the governor-general with defective advice that would have extended, not resolved, the parliamentary deadlock, leaving the governor-general with no alternative but to act.

Indeed, Mr Whitlam had already sent a senior minister to let the governor-general know just how important it was that the supply crisis be resolved quickly, for fear of damaging the Australian economy. Mr Whitlam was the architect of the dismissal, not the governor-general.

David Smith, Mawson

With interstate visitors, I recently walked around the Australian National Botanic Gardens on the lower slopes of Black Mountain, off Clunies Ross Street, Acton.

If Canberra is the Bush Capital, the Botanic Gardens reflect it beautifully. The gardens contain the world's most comprehensive display of living Australian native plants. Children can be educated by the displays along the tracks leading from the parking area. And there is an excellent restaurant with friendly staff.

The local tourism authorities should do more to publicise this botanical gem hidden under the foliage of Black Mountain. I highly recommend it for a lunchtime outing.

John Milne, Chapman

Presumably in response to Simon Corbell's claim (''Rail benefits 'beyond economic''', July 16, p1) that social benefits justify the Gungahlin- Civic tramway (despite a cost-benefit analysis showing it wouldn't be economically justified), Professor Leo Dobes (''A simple sanity check on ACT's light rail'', Times2, July 17, p5) says: ''Social cost-benefit analysis is designed precisely to capture all of the benefits to society.''

That's true. But my experience of cost-benefit analysis (from my Treasury days) is you should take such an analysis' measure of ''social benefits'' with a grain of salt - because some ''social benefits'' are immeasurable. For example, how much confidence can you have in putting a monetary figure on such benefits as reducing congestion, people living in one place rather than another, employment in one place rather than another, the value of land in one place rather than another, or saved time etc.? An American professor once told us a cost-benefit analysis showed a new port was justified by including the ''benefit'' of the ability to fish in the harbour.

That's why Corbell is justified in trying to justify the project for non-economic reasons - even though he hasn't, because the cost of extending the bus service would obviously be lower for Canberra taxpayers.

R.S. Gilbert, Braddon

The Yarralumla Residents Association does not share David Dawes' definition of community engagement (Letters, July 14) . Genuine community engagement involves regular dialogue rather than three years of silence between consultations.

Genuine consultation means responding to community concerns. The community expressed concern in 2010 about the density of the proposed Canberra Brickworks and environs development.

The LDA responded by increasing density from 1100 to 1600 dwellings, and increasing maximum building height from four to eight storeys. It provided a short period to comment on a massive development that will double Yarralumla's population, and affect all Canberrans using Cotter Road, Yarra Glen and Adelaide Avenue. Genuine consultation also means providing the community with the information needed to make informed comment.

Instead, the full Canberra Brickworks and Environs Planning and Development Strategy was not made public until part way through the consultation period. Our association had to seek consultants' reports through freedom of information. Sadly, the current proposal ignores most community concerns raised previously. In our view, it does not meet many of the LDA's own stated objectives and claims for the development.

Marea Fatseas, president, Yarralumla Residents Association

I've walked my dog in Kambah daily for over 10 years and have often been appalled at the amount of litter strewn about our streets. Monday morning is garbage collection time in my neighbourhood and while walking the pooch, I witnessed a recycle collection truck rumbling with litter bellowing out. Based on that, I reckon about half of our litter problem is caused by these vehicles.

Doug Mulley, Kambah

WELL-PLAYED, GREENS

With the demise of the carbon tax/ETS legislation, I would just like to say: ''Well played, Australian Greens!'' How wise and far-sighted they were to side with the Coalition in blocking the Rudd Labor government's Carbon Pollution Reduction Scheme! After all, part of a loaf is worse than none.

D. McNeill, Rivett

EERIE CRASH REMINDER

Congratulations to Chris Fowler (Letters, July 22) for his timely reminder of another eerily identical incident - a civilian airliner shot down in 1988 by the USS Vincennes with the loss of 290-odd lives including ''no fewer than'' 66 children. The only difference between the two incidents is our response.

Fred Pilcher, Kaleen

RUSSIA WORLD CUP BAN

If the rest of the world is serious about consequences for Russia's actions in Ukraine, why is no one suggesting maybe Russia is no longer suitable as the host of the 2018 FIFA World Cup?

Julie Long, Kambah

AIDS TOLL COMPARISON

Michael Kirby thoughtfully implied on ABC's Q&A that while MH17 was tragic, millions of people have been killed by the AIDS virus and millions infected have no medication. Statistically, over a million people die each week from all causes.

Rod Matthews, Fairfield

TREES CHOPPED DOWN

Tree Week in Canberra is being celebrated by the removal of four trees on the west side of West Row outside Canberra House!

Gail Tregear, Civic

CONSTRUCTION CURE

How refreshing to read Tony Lane of Vincents' receivership firm's assessment of what is needed to fix the construction industry. None of this populist stuff of building a new convention centre or throwing borrowed money at the problem under the guise of ''stimulus'', just get rid of the red tape and union-inflicted ''hurdles'', such as ''training'', which suffocate the industry.

Brendan Ryan, O'Malley

THANKS TO HELPERS

Many thanks to all the kind people who rushed to my aid when I had a bad fall on the Hindmarsh-Yamba pedestrian crossing at 10.45am on Friday, July 18. May their good karma be returned a thousand-fold.

Elizabeth Swanton, Swinger Hill

SILENCE OVERRULED

While I understand the horror expressed by Edward Corbitt (Letter, 22 July) at the fireworks during the minute's silence for the passengers of MH17, I am not surprised. Anyone attending a Brumbies match must realise any form of silence is not to be tolerated.

Paul Morton, Weston

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