The Top Gear presenter was responding to abuse he received from Twitter trolls after announcing that his dog Whoopi had died.
"A few moments ago, my dog died, and, as an experiment, I announced the fact on Twitter. Now, everyone must have known that when a family pet is put down, the family in question is bound to be upset," Clarkson wrote in Top Gear magazine.
"So you'd expect a bit of sympathy. And, in America, that's what you'd get. Not in Britain, though. Moments after I posted my tweet, Adam Farrow said the news was 'kinda funny'.
"Phil May wanted to know if it was James May's fault, and Tom Green said simply, 'Good'. All that in less than what Twitter calls zero seconds.
"Five minutes has now elapsed, and still it's a non-stop tirade of abuse. Which confirms my theory. Britain is a nation of 62 million complete and utter b**tards."
Clarkson continued: "We are the country that invented the concentration camp, and international slavery. Hanging, drawing, quartering: that was us too.
"And who was it that sent the White Russians home to be slaughtered by Stalin? Yup. Us. Outwardly, we hated communist Russia; inwardly, it's what 95 per cent of the country wants.
"Bankers, estate agents, politicians, journalists. Anyone in a suit is basically evil and must, after they've been sacked, go to prison. Anyone in a donkey jacket? They're basically good and must have a plasma television immediately."
Clarkson previously vowed to 'find and kill' cyber bullies.