Are you seriously suggesting that England should not have gone to war against Hitler?....Actually, I guess you are. The quote was referencing that very attitude in GB at the time. Chamberlain's refusal to deal with the Nazi's as they rose to power, led directly to the terrible loss of life when they were finally forced to confront Germany at the height of their power.
We are not in Afghanistan to prop up a corrupt regime. We are there to kill the Taliban while we are still able to do so..
England failed to confront the nazis when it would have been easy, and chamberlin painted himself into a corner that brought england into the war. Hitler's original intention was to focus on russia, but changed his plans once england entered the war.
Of course its hard to argue against waging war on the nazis, but if we look at this starting from world war I, which england very much wanted and suffered from greivously, the punitive armistice that lead to debasement of the currency and rise of a german totalitarian government, its possible to see churchill in something other than the self-congratulatory light he shines through his writing.
In any case, when invoking churchill, its best to recall that churchill oversaw the reduction of england from empire to irrelevance. Now, I don't think the US should be an empire, but let's bear in mind that even victors of wars can find the wars most regrettable.