[peisistratos]

As workers tend to have one goal, to have less of their labor time expropriated, there really isn't a reason to have more than one global union. Walmart has over half a trillion in revenue and over two million workers, and it makes sense a union containing those workers be of that size.

Also, if carpenters work for UPS, should they be in the carpenters union or the Teamsters? Large industrial unions do away with such jurisdictional problems.