Variants of Leftism

Here's Frank Warren comparing the US 'Popular Front' liberalism of the 1930s to the Cold War liberalism of the 1950s:

The Popular Front liberals, with their simplistic ideology and sentimental unity of ‘progressives,’ betrayed a moral callousness toward those who suffered under Stalin’s crimes. But the contemporary liberal, with his new found knowledge of totalitarianism, his hard-headed, realistic, tough-minded pragmatism, has temporised with social ills, avoided conflicts with conservatives in the name of consensus, suggested and justified outrageous actions in the name of the ‘free world’.

I don't think either category has entirely gone away.