One of the greatest ironies of the latest episode of the "Mr Trump goes to Washington" soap opera is that a bait and switch operation by a clever lawyer who wanted to talk about laws that stop suspected Russian human rights abusers from entering the U.S. could be what brings the house of cards crashing down.

Natalia Veselnitskaya, the Russian lawyer who contacted Donald Jr. through an intermediary in June last year offering incriminating information about Hillary Clinton, has since said she was not an agent of her government and that she had not passed on any information.

The second part of that claim tallies with Donald Jr's. account in which he states he terminated the meeting when he realised he had been had: that Ms Veselnitskaya had a separate agenda and that no dirt file on Hillary Clinton would be forthcoming.

The first part, that she wasn't acting for the Russian Government, is open to question given President Putin's hostility towards the controversial Magnitsky Act, which directly affects some of his friends and cronies, is well known. He responded to its introduction by banning the adoption into America of Russian orphans.

These issues, while interesting in themselves, are not the reason for all of the attention however.

The media circus is all about what Donald Jr. was told ahead of the meeting, which was also attended by Donald Trump's son-in-law, Jared Kushner, what he expected to learn from it and, most importantly, whether or not he discussed it with his father.

One of the most striking similarities between the ongoing investigation into possible collusion between the Trump campaign and the Russians and the last couple of times the question of impeaching a Republican president arose is that they all come down to what the president knew and when he knew it.

That was central to both Watergate and the Iran Contra scandal and the same applies now.

If it can be proved that as early as June 2016 Trump knew key members of his campaign were setting up meetings with people they thought represented the Russian Government in the hope of securing information that would damage the Democrats the end must be near.

All the tweets, statements, obfuscations and denials that have been issued from his phone and the Oval Office will be revealed as just "fake news" from the political trenches by a grandstander obsessed with hanging onto a job he is not qualified to do.

If this does come to pass then what is currently the world's favourite reality TV program is unlikely to make it into a second season.