This is the conceit so dear to Bay Area lefties. They so want to see themselves as idealists bravely standing up to "oppressive regimes" that they have convinced themselves that a public transit agency run by elected officials in the most liberal metropolitan area in the United States is analogous to Egypt's or Libya's Mukhabarat.
In order to feed that fantasy, they put on masks, pick on BART police and block other people on their way home from work. Unlike Egyptian and Libyan protesters, they have little to fear -- except the day when they grow up and find themselves on the receiving end of such tantrums.
Something Good Out Of Congress: No More Taxpayer Dollars to Presidential Political Conventions | Heather Ginsberg