Very few American police officers get shot. It's an imagined threat, like terrorism: http://m.huffpost.com/us/entry/6373798.

And yes, people should be able to own at least some kinds of guns. Though, I think you could constitutionally ban handguns: the 2nd amendment exists to let the people defend the homeland against external threats and possibly the government, not for personal defense. It's automatic rifles that people should be allowed to own.