Thomas Struth, Art Institute Of Chicago II, Chicago, 1990
This installation of thousands of yellow construction helmets posted in front of Milan’s stock exchange represents a Labor Day protest of unemployed Italian workers. Learn more here.
Bonus: the sculpture in the middle of the plaza is by Maurizio Cattelan and has its own interesting history.
Art as protest.
Thomas Cooper Gotch
'The Lantern Parade', 1910, oil on canvas
'Study for the Birthday Party', about 1930, oil on canvas