Well that depends on your definition of Radicalism, you clearly mean it in the context of Radical Leftism, ie Socialism/Communism, I mean in the the context of British politics, ie the Radicals in the early Liberal party etc, meaning just the advocation of heterodox ideas not currently in vogue, so it's relative to the times. Gay marriage used to be radical, now it's not, gender equality used to be radical, now it's not. You know?