I was able to check our position a couple of times using an app on my iPhone that utilises the inbuilt GPS, even when out of service range. This was accurate to within three metres.

To propose that our naval commanders of multimillion-dollar ships, with all the latest navigation equipment and expertise, did not know (seven times!) where the waters of another sovereign nation began because it was a complex archipelago is ludicrous.

More likely these diligent public servants, with massive duties of care for our security and safety, are being hung out to dry for interpreting and putting into action an illegal and obscene policy.

This is a form of (moral) corruption of two politicians far worse than anything unfolding in NSW.

Peter Blunt, Theodore

Although the names of the naval officers disciplined for straying into Indonesian waters during Operation Sovereign Borders have not been released, I suspect they could well be Captain Scapegoat and Captain Patsy (''Navy captain stood aside, another punished over Indonesia breaches'', April 17, online).

The two sailors may have felt they were carrying out orders from Admiral Scott Morrison, but they are merely collateral damage in Field Marshal Tony Abbott's battle to win a second term in 2016.

Mike Reddy, Lyons

On SBS on Thursday, we were shown the fast-widening gap between the rich and poor people in England. Every day, 913,000 people need to go to a food bank or charity so as to survive and be able to give their children something to eat.

On the other hand, we have a couple of royal idlers spending millions of dollars by travelling first class, and being slim of body by choice and not because they cannot afford to buy food for their family.

How can those people not feel the shame of flaunting their wealth when so many of their compatriots are starving? Haven't they any moral values? Are they so out of touch with the world to see it the way it is? How can they live with themselves and how can one not be disgusted by their ostentation?

There is nothing wrong with being wealthy if you have earned it honestly and know what real work is.

G. Coquillette, Spence

The Canberra Times' front-page headline (''Canary Kate and kin dazzling in the Emerald City'', April 17) made me recall what Oxford scholar A. N. Wilson said in his book The Rise & Fall of the House of Windsor.

Evidently, when the Queen or members of the royal family travel abroad, a bill for their travelling expenses, including suits, shirts and outfits, is sent to the British embassy of the country they happen to be visiting; the bill is then sent back to the Foreign Office in London, and is paid by the taxpayer.

With such an arrangement, the Duchess of Cambridge should have no difficulty in dazzling the crowds for many years to come.

Sam Nona, Burradoo, NSW

The visiting royals may be ''the world's most iconic couple'' and might very well be lovely young people, but does that mean they and baby George should eventually ''reign over us''? Why should Australians, who see themselves as so egalitarian, accept as their rulers the hereditary monarchs from another country?

Surely there are plenty of Australians who could fill the position of head of state on merit rather than by birth, and would represent our own country first and foremost.

If Australia became a republic, it could still be a member of the British Commonwealth and we could still swoon over Britain's royals.

But let's not confuse celebrity with the rule of our country.

Gail Ford, Kambah

I notice Werriwa MP Laurie Ferguson still has his doubts that Badgerys Creek is the right site for Sydney's second airport: ''I have grave doubts about the applicability of studies that are decades old and lofty visions of infrastructure and jobs'' (''Roads come first, then the airport'', April 16, p6).

During the 1960s, I was the principal planner in the NSW State Planning Authority responsible for preparing and implementing the 1968 Sydney Region Outline Plan, which established that the best available site for a second city airport was at Badgerys Creek, together with contiguous areas that lay under the likely flight paths (airport noise zones) where residential development would be restricted, but the land would not be acquired by the Commonwealth.

Working with the Department of Civil Aviation, the following areas were evaluated for best suitability: the RAAF air base at Richmond; the Royal National Park in Sutherland Shire; Badgerys Creek, Liverpool; Gosford Plateau, west of the Pacific Highway; the RAAF air base at Williamtown; and a Sydney Airport expansion at Towra Point on the opposite side of Botany Bay.

The airport prototype was modelled along the lines of London's curfew-free second airport at Gatwick, envisaging that aviation facilities (terminals, runways, etc) would be complemented by substantial numbers of factories, warehousing, commercial offices, air transport companies and so forth, as sources of local employment.

The Department of Civil Aviation's target deadline was to acquire the site as soon as possible in order to stabilise land values and for the authority to begin construction by 2000, when , it was estimated, Sydney's population would be about 2.7 million.

The federal government's acquisition of land for the Badgerys Creek site began in 1971 and the decision to proceed has just been made, 46 years later, when Sydney's population has reached 4.8 million or thereabouts.

That is about par for the course in Australia.

Tony Powell, Griffith

The voice of innocence: ''Daddy, do you get thank-you notes after you give people presents and things?''

''Quite often, darling.''

''How long do you keep them for, Daddy?''

''Oh, just a few days or so, darling.''

''Do you keep them for three years because they might prove useful to you at a later date, Daddy?''

''That note was probably kept on a proper file. Go straight upstairs to bed and stop trying to be a suspicious little Miss Smarty Pants.''

Bill Deane, Chapman

The vandalism at the Canberra Islamic Centre again draws attention to the continuing cost to community organisations of the scourge of this crime (''Centre's vandalism condemned'', April 15, p3).

Canberra MP Gai Brodtmann says the damage at the centre speaks of hatred and malice. Others say the attack was motivated by bigotry.

Perhaps so, but what motivates the frequent vandalism to schools, churches, Scouts property, private dwellings and cars, for which the annual cost is enormous?

It is clear the attack on the Islamic centre caused significantly greater damage than much of the vandalism apparently accepted in Canberra as a fact of daily life.

Too often this wanton destruction is blamed on some government policy or lack of facilities for underprivileged people. But the properties damaged are generally built and maintained by volunteers or by the government on behalf of residents, who in effect pay for it. Voluntary organisations rarely receive support, financial or otherwise, to remedy damage caused by vandals.

So it is encouraging to see the support given to the Islamic centre, particularly by the principal of St Mary MacKillop College, Michael Lee (Letters, April 17). This open-minded man was criticised by some when he appointed a Muslim as college captain in 2011. Lee's example and that of those helping to restore the centre can see some good come from this destruction.

Meanwhile, there can be no justification for vandalism, regardless of its motivation. Which is why the support by former Greens MLA Caroline Le Couteur for an attack on the Parkwood chicken farm in March 2012 stands condemned.

Choosing as she did to thank those who damaged that property suggests vandalism can be justified if the vandals believe their cause is just.

Graham Downie, O'Connor

The attack on the Canberra Islamic Centre last weekend shames us all.

My own experience of the centre has been of a vibrant multicultural institution that not only serves its diverse community but reaches out to promote harmony and understanding.

It is difficult to understand what could have motivated this criminal violence that is so at odds with mainstream Canberra culture. If fear of ''Islamic extremism'' is the issue, the centre is the wrong target. In any event, this phenomenon has little presence in Australia and a very small one in our region.

As Greg Fealy relates (''Political Islam on the rebound in Indonesia'', April 16, Times2, p5), recent Indonesian elections saw a small increase in support for Islamic parties - the secular parties dominated - but this was based on campaigns that were ''invariably inclusive and universalistic'' with no mention of Sharia law.

About 90 per cent of Indonesians identify as Muslims. Some in our community exhibit particular fears about Islam and Muslims, though popular figures like Waleed Ali demonstrate a mainstream Australian Muslim character and personality.

Diana Abdul-Rahman is another role model and a significant figure in the Canberra Islamic Centre.

Those who committed the crimes must be brought to justice quickly.

More importantly, the view that anti-Muslim bigotry is unacceptable should be strongly expressed and reiterated by our community leaders.

Peter Dawson, Hughes

The broad-based support (and practical help) pouring in to restore and protect the Canberra Islamic Centre is accomplishing something very special.

Indeed, the alchemy of kindness is creating a little miracle of love. The dark cloud we saw last Sunday now has a silver lining that is bringing our community together in a most remarkable way.

Ross Kelly, Monash

The principal of St Mary MacKillop College, Michael Lee, has established his college as a centre of subtlety and scholarship by his letter (April 17).

At issue is his insight that it might be found that the vandalism of ''the Islamic community centre was based on bigotry, sectarianism and the Islamic faith''.

If the acts are an extension of the violent, worldwide and centuries-old bigotry between the Sunni and Shi'ite sects of Islam, it is indeed ''particularly disturbing for all of us'', as Lee observed.

Gary Wilson, MacGregor

It's good to see generous Canberra people helping clean up the mess in the Islamic centre.

I would point out though that in the countries where Islam rules churches and synagogues are ruthlessly desecrated and destroyed, Jews and Christians savagely persecuted, and it would be a courageous Muslim neighbour who helped clean up there.

J. Halgren, Latham

I see that Boko Haram, the Islamist terrorist group in Nigeria, have finally met their match (''Nigerian schoolgirls taken to Islamist stronghold, say parents'', April 17, online).

What on earth were they thinking: abducting more than 100 schoolgirls aged between 15 and 18?

Any parent of a teenage girl will tell you that it's hard enough managing just one of them, let alone 100.

I can only think that Boko Haram turned them loose in despair and the one gang member captured turned himself in for his own safety.

Dallas Stow, O'Connor

Nicky Hussey says it's good more people will ride motorbikes to work in response to parking charges (Letters, April 17).

But in reality it's just parking costs inducing more people to take more risks with life and limb.

Riding bikes is much more dangerous than driving cars.

Many people aren't up to it.

Compare road accident death and injury statistics.

In terms of hospitalisation for injuries, per participant, motorcycle riders are rivalled only by bicycle riders (who face no licence tests). People contemplating riding bikes in traffic must be made fully aware of how much more dangerous it is.

Cars educate inexperienced/incompetent drivers by (usually) allowing small mistakes without the serious consequences.

For example, bike riders take years to accurately deduce how their bike behaves when cornering in the wet on different, uneven road surfaces.

Drop that bike and you're run over or your body strikes an immovable object.

Cuthbert Douglas, Bonython

POLLIE MEMORY LOSS

Barry O'Farrell joins a long list of politicians who suffer from a strange and damaging affliction known as ''spontaneous memory loss'' (''Premier wrote his own downfall'', April 17, p1). Common to people in high office, it is virtually unknown in the wider community.

H. Ronald, Jerrabomberra, NSW

DOUBLE STANDARDS

When questioned about Barry O'Farrell, Tony Abbott said we need high standards from the media. Where was he when Alan Jones said Julia Gillard should be put in a chaff bag and towed out to sea?

John Gelling, Murrumbateman, NSW

CHEAP SHOT'S BEST

''Cheap wine and a three-day growth'' sure beats an expensive one while looking squeaky clean!

Greg Simmons, Lyons

UNFORGETTABLE BLUE

My mate Igor gave me a six-pack of Toohey's Blue in November 1993. I'll never forget it.

Ned Ovolny, Duffy

RELATIVE INTEGRITY

I think I need to buy a new dictionary. The definition of ''integrity'' in mine, based on recent usage by prominent public figures, seems to be wrong.

Brian Smith, Conder

MORE POLLIE LOSSES

How can one explain the persistent memory failure of senior figures within the conservative side of politics? John Howard and Alexander Downer at the Australian Wheat Board inquiry; Arthur Sinodinos at ICAC; and now Barry O'Farrell, also at ICAC. How can anyone have confidence in leaders whose memory retention is so poor? One wonders how many other lapses have not been uncovered.

David Nolan, Holder

WHAT GOES AROUND …

So St George wants the two competition points from its match against Melbourne, as it believes full-time should have been called before Melbourne scored its final try. St George took a (competition) point off the Canberra Raiders in exactly the same fashion in 2002. A case of swings and roundabouts, perhaps?

P. Murphy, Gungahlin

IPA ANSWER TO ABC

Julie Novak's article ''ABC must get with program'' (Times2, April 16, p1) arrives at the predictable Institute of Public Affairs conclusion: all public services should be delivered by gouging corporates, all debate challenging the plutocracy must be curtailed and ''free speech'' is solely the prerogative of the establishment.

Albert M. White,

Queanbeyan, NSW

Email: letters.editor@canberratimes.com.au. Send from the message field, not as an attached file. Fax: 6280 2282.Mail: Letters to the Editor, The Canberra Times, PO Box 7155, Canberra Mail Centre, ACT 2610.

Keep your letter to 250 words or less. References to Canberra Times reports should include date and page number. Letters may be edited. Provide phone number and full home address (suburb only published).