Not content with upstaging Kerry’s French kiss (‘our oldest ally’) – Obama gave us Brits a hug (‘our closest ally’) – the Prez entered even deeper archival waters with a reference to the USA as ‘the oldest constitutional democracy’.
Well! Where to start? If he had said ‘written’ it would be easier to swallow – since our well-informed schoolboy is aware that the UK’s constitution ain’t – at least not in one convenient volume; and nor was the constitution of any of the other oft-quoted candidates for the honour – like Ancient Greece, Iceland or the Isle of Man. We of course prefer the term ‘parliamentary’ to make our claim to being first, ignoring inter alia the three just mentioned.
But why, you may ask, did Obama make the claim at all? Backside is of the opinion that the White House speech-writers cannot resist any opportunity to reasssure the citizenry that Uncle Sam might make warm noises about his friends abroad but they’d better not forget who really brought power to the people first. In the beginning was Uncle Sam. The word was with Uncle Sam and the word was Uncle Sam. Amen.
Boadicea's Chariot 
Unfortunately, Americans are taught no history but their own – and that has been written so that they think they invented everything, – including the wheel,
OK – so I exaggerate – but only a bit!
I recall listening to an American pontificating about George Washington’s whiskey distillery. I quote:
It amuses me that so many Americans are proud of the fact that they threw out the British monarchy, which even then had limited power, and replaced it by a President who can take the country to war with no reference to those elected by the people.
At times I wonder if the USA is as much a cult as it is a country. After all, the mythology surrounding it and its history requires such absolute faith and acceptance without critical reasoning that it takes on almost religious qualities. This absolute faith can become troublesome, especially since so many take it as a personal assault on their honour if it is challenged — no matter how much historical facts support the challenge. I was disowned by an uncle and his family for saying that the USA and its poorly thought-out meddling helped to de-stabilise Europe and the Pacific Region, for example.
That said, the USA does still have its successes.Its written constitution is presently the oldest, its government is one of the oldest still in existence and it has contributed a lot in its relatively short history — not as much as it thinks it has, but still a lot.
I think Christopher has a very fair analysis in #2.
Re the yanks knowing no history, not really true actually, but a good breadth of history teaching is just the same as the UK, limited to the upper echelons of the educational tree. Unfortunately seemingly not many of them become politicians! Or if they do they adopt the carapace of #2 as a self defence stance.
I think the crack about Washington has been misunderstood. He was in fact the richest man in America at the time, his holdings in both land and industrials were huge. His assets would have put him well up in the premier league anywhere in the western world.
I think this area is one where the UK and the USA diverge with extremity. The British just love to ‘bad mouth’ their own country and the Americans just ‘big up’ theirs. Neither understand each other’s psychology.