Anthony Hilton: AIG's great escape is an omen that RBS and Lloyds will one day be out of debt

That single bailout, it should be noted, is more than the current UK budget deficit

The unexpected highlight of my week was to be in the room in the Lloyds Building on Tuesday when Bob Bernmosche, the chief executive of AIG (American Insurance Group), announced that as of the previous evening his company owed the taxpayer nothing.

This was an historic moment. After all, it is not every day you hear a company has paid back $184bn (£114.1bn).

AIG, at the time the world's largest insurance company, was at the heart of the financial crisis. It was the firm which had decided in a moment of madness to insure credit default swaps ( against default) and in so doing it made securitised bonds acceptable to a whole range of investors who otherwise would never have touched them. This in turn fuelled the explosion of credit, the sub-prime bubble and all the other excess that followed.

And while we British taxpayers think we were so hard done by after putting £40bn into Royal Bank of Scotland (RBS) and Lloyds to keep them afloat, the US taxpayer injected three times that into AIG, because if it had been allowed to collapse it would have brought down all the banks in America and across the world who were relying on it paying out on those default policies.

That single bailout, it should be noted, is more than the current UK budget deficit which George Osborne is finding so difficult.

Restoring the fortunes of the company is an astonishing achievement, because when Mr Bernmosche picked up the reins – he was not from AIG and indeed came out of retirement to sort out the mess – the business was trying to repay the US government by selling off its assets at rock-bottom prices.

He quickly realised that this would leave them well short of what was needed but he then had to persuade the politicians, the regulators and indeed those in the business who included his own chairman that they should stop the fire sale because AIG could be rebuilt. That was probably the hardest part of the job, and his neck was put firmly on the line.

Almost everyone else believed the crash had tarnished the AIG brand so badly no one would ever want to insure with it again. But in fact the business lost only about 10% of its customers – though it had to drop prices pretty sharply to keep some of them. Today, while there is still some lingering sucking of teeth at the mention of the name in the US and parts of Europe, in the rest of the world it is as if the scandal had never happened.

Thus it was that on Monday of this week, the US treasury sold the last of its shares, meaning that not only had the $184bn been repaid in full but government has actually come out with a near-$20bn profit.

If a company of that size can be sorted out and turned round in four years, then we ought reasonably to expect that one day, before too long, RBS and Lloyds will also be able to come out blinking into the sunlight.