As no foreign soldier has set foot on American soil since the Anglo-American war of 1812-15 (in the course of which the Brits torched a fair swathe of Washington DC, including the White House), and the US has assembled the mightiest military machine in history, it seems a bit paranoid to believe that, if it wasn't for all those guns under all those beds, Nazi/commie/yellow/Muslim hordes would be rampaging through Smalltown, USA.
Likewise, this business of playing Russian roulette with the US - and therefore the global - economy every few months is wearing a bit thin.
But while some spectacularly clownish politicians get elected in America, we should bear in mind that people in glass houses shouldn't throw stones. World markets went sideways this week at the prospect of that grubby old demagogue Silvio Berlusconi once again getting his hands on Italy's levers of power and plunging the eurozone into another crisis.
Some dreadful duds, shonks and dimwits have been voted into our Parliament, and their numbers will only increase since MMP means you don't necessarily have to go through the (admittedly not foolproof) weeding out process of trying to persuade people to vote for you.
The US can't seem to get through a decade without blundering into a war, but at the risk of appearing flippant, it's a dirty job but someone's got to do it. Blunder into a war, that is. The US might sometimes be heavy-handed in its role as the world's policeman, but nobody else is volunteering for the gig.
It's often said that Americans don't get irony. Having lived in the UK, France and Australia, I can attest that plenty of people in those countries don't get irony. As a columnist who doesn't mind a bit of irony now and again, I can also attest that not all Kiwis get it either.
Only people who don't watch American TV or movies, read American books, follow American public affairs or listen to American music could possibly make the blanket statement that Americans don't get irony. That being the case, it says more about them than the people they're sneering at.
The most interesting thing about the perception of Americans as stupid is that it doesn't make an iota of difference to America's cultural dominance. Indeed, it sometimes seems that the more the rest of the world patronises the US, the more voraciously it sucks in America's cultural exports, the more slavishly it imitates American fads and fashions.
The 20th century was the American century for reasons that went beyond its economic and military predominance. As the Chinese will discover, global influence is not just GDP and aircraft carriers. US popular culture caused the world to fall in love with the idea of America; stupid or not, there's no sign of that love affair cooling.
Van Morrison's song Cleaning Windows is about growing up in Belfast, Northern Ireland, in the 1950s and 60s: "I heard Lead Belly and Blind Lemon on the street where I was born/Sonny Terry and Brownie McGhee/Muddy Waters singing 'I'm a rollin' stone'."
Meanwhile in London, Mick Jagger and co were listening to the same music and trying to think of a name for their band.