The NATO protests kicked off with a two-hour rally in Daley Plaza hosted by National Nurses United, part of a "global week of action"—including rallys in Europe, Africa, and Mt. Fuji—in support of, among other things, a "robin hood tax" on financial trades (hence all the Robin Hood hats) like the one proposed by economist Joseph Stiglitz. The rally filled Daley Plaza, mostly the red-shirted nurses, filled in by Occupy Chicago protesters and a few folks protesting Scott Walker, the military, and a handful of other things.
Early on, a speaker on stage addressed the negative media coverage of Occupy, which has at times bordered on the surreal and/or absurd. I personally witnessed one such moment while watching WGN local Chicago news in the morning when a film reviewer suggested "anarchists" would be throwing "bags of feces" at the NATO protests right before giving Battleship" a "B+."
Afterwards, protesters went off an an unplanned march up Michigan; more on that in a bit. Two salient observations: "Chicago is so weird right now. Like a busy Sunday w/ more cops." (Yes—a sprightly mix of protesters and tourists.) And: "Police are seriously chill. Think they're waiting for protesters to get bored."