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They've always been a bunch of sweethearts. Organized in the 1890's as the ILA, they conducted a series of unsuccessful strikes in the first two decades of the 1900's, finally hitting their stride on "bloody Thursday" - July 5, 1934. Three years later, the Pacific Coast longshoremen broke away to form the ILWA, affiliated with the CIO. This didn't last long; following a dispute in 1948 over their Leftist leadership and general thuggishness, the CIO expelled them. They were fairly quiescent for a couple of decades, but started acting up again in the early 1970's - and they've pretty much been butts ever since.
In context, then, the idiocy seen out of them in Longview, WA. of late is standard behavior for them. It's all they know.