Occupy Oakland has jumped the shark with today's "general strike". From a population of over 7 million (in the San Francisco Bay Area), they managed to assemble maybe 7000 people. Based on this support from 0.1%, they felt that they had the prerogative to shut down the Oakland Port and disrupt the lives of the people who work there. I haven't heard from the organizers, but I can't imagine any reason that the port would be viewed as particularly evil -- it seems that they were just looking for a choke point in the local and national economy.
Protests shut Oakland port, tensions flare in streets | Reuters
If you're pissed at the government, then block government buildings. Leave the port alone.