Have you heard the one about Obama? I'm afraid I can't tell you because, along with probably everybody else, I haven't heard it either. I watch my fair share of TV panel games and listen to Radio 4 quiz shows, both of which are now stuffed to the gills with an apparent never-ending supply of comedians, and the US president seems to get a remarkably easy pass despite the regular opportunities for mockery which have arisen over the course of a term and a bit in office. Bush, Cameron and, of course, Margaret Thatcher in her day, should have been so lucky.
It's not just the Democrat in the White House who seems to be a sacred cow as far as modern comedy is concerned. The environmentalist movement remains similarly untouched by our brave, envelope-pushing comics, along with even the wackier workings of multiculturalism and, heaven help them, radical Islam. Anything, however, which smacks of conservatism in any form remains fair game, along with "mainstream" tastes, Tory politicians and lately (and rather lamely) the Queen. The staples of sexism and racism have been banished, and that can only be good, but the space left behind has been occupied by a monolithic and equally prejudicial political correctness.
This is not to say that our comedians are overtly political, or at least not all of them. Rather, whether it is the peevish snobbishness of David Mitchell, the permanent two-fingered salute of Jo Brand or the smart-alec smirking of Jimmy Carr and Robert Webb, the overall impression is of a self-satisfied, predictable sort of knee-jerk liberalism. Modern comics might call themselves stand-ups but they seem to see themselves first and foremost as satirists. They compete with each other to see who is the cleverest, the most cutting, the most "edgy" — and woe betide anyone who "sells out".
If the drooling critics and profile writers of the broadsheets are to be believed, we have been living in a golden age of comedy, one in which new personalities arrive three at a time and become the darlings of these mostly metropolitan writers lovingly dissecting their heroes' art. Comedy is all around us, taking over stadiums and selling out on DVD. Only a hopelessly stuffed-shirted killjoy could fail to be rolling in the aisles.
And yet, strangely, it really does sometimes seem as if there is less and less to laugh at. Certainly the public, or a particular section of it, might go wild every so often for a hyped-up new sensation; right now the retro, knowing slapstick of Miranda Hart is flavour of the month, just as before it was the one or two catchphrases of Catherine Tate, or the nastiness of Little Britain. But despite all the trumpeting, such newly discovered all-time greats seem to fade as quickly as they arise.