For more than 125 years, May Day also has been considered International Workers' Day, which we Americans eventually chucked to another time on the calendar (Labor Day, at summer’s end) so as to avoid confusion with the Commies.
I personally stick to pre-summer, primarily to avoid embarrassment such as that appearing each year around this time at Freedom to Screech.
Their (labor) movement pushed to better the conditions of the work place and strove to secure respect and appreciation for those who work hard. Now it seems like some unions are destroying our country.
If we really must, then here's a reprint worth reading.
REWIND: Will work for something real.
For Labor Day weekend consideration, here's a look back at a thoughtful piece about economic development from YES! Magazine's David Korten, reprinted in its entirety under a Creative Commons license. It originally was posted by Bluegill on Sept. 6, 2010, and you may find it useful to turn to the comments section there, where a spirited discussion ensued.