By coincidence I just stumbled across a post that my crazy-ass liberal friend Leonard Pierce wrote for his blog that also mentions the WPA posters, and he fully fleshes out one of the truest (and most touching) points one can make about them:
I recently came across an archive of posters created by and for the Works Progress Administration under FDR, the man I will never stop thinking of as the greatest president America has ever had. I highly recommend it for its incredible aesthetic beauty, but there is more to it than that. Looking through each one, seeing what programs it was intended to support and what goals it was designed to achieve, is like glimpsing an alternate universe where the government actually cares for its people — and does something about it. Each poster reflects the values of a political class who believes that everyone in its sphere of influence — nursing mothers, workers who might want to learn more about current events, unemployed people who have a skill or a trade that might be worthwhile to someone who doesn’t know them, retired people who have mastered a craft in their old age, girls who want to learn magic tricks, musicians whose careers have been shipwrecked by economic turmoil, farmers who need to find about about advancements in agriculture, kids who are interested in science but don’t have proper books, local artists trying to make a living, tourists, writers, tenement dwellers — is valuable. It is this recognition that everyone has potential, worth, and value, and that by supporting a system that valorizes the privileged and ignores the poor, the nation is cheating itself on every level, that helped lift the nation out of a murderous depression. It was this conviction that created the best-educated working class America has ever seen, quelled a century of labor strife, and laid the foundation for the liberal consensus of the post-war world that led to the longest single period of economic prosperity the country had ever seen.