Yglesias stumbles onto an interesting intellectual exercise. Could we have a CCC or WPA in 21st Century America where nearly 37% of all public employees are union members and a much larger percentage of public employees are part of a collective bargaining unit?
My off the cuff answer is that certainly it could be done but it would be difficult. I know, very helpful - right?
I have no idea what the public sector union density rate was in 1933 when the CCC was founded. The legal right to join a private sector union was codified in 1935. Prior to the Wagner Act private sector union density was less than 7%. I think it would be fair to say that public sector union density was certainly no higher than that and likely much lower.