Political activism may have no place in science, but science absolutely has a place in politics, unless by "[t]he sciences should certainly exist outside political activism" you mean that politicians should just accept the general consensus of science as fact when making, enforcing, and adjudicating laws. A United States of America where scientists and science-minded people do not get involved in political activism is a United States of America that "teaches the controversy" of creationism in schools, bans stem cell research because babies, and denies that climate change is occurring. Well, I guess 2 out of 3 ain't bad...