There was a big public outcry and support for giving police the "tools they needed" to be able to take on the better-armed criminals, gangs, and drug dealers.
So now that the police have become essentially local armies in many jurisdictions, people think they have gone too far.
What troubles me most is that neither Obama nor most legislators in congress have the first clue or any experience in law enforcement. So anything that happens is going to be driven by political concerns, not what makes the most sense for effective and appropriate law enforcement.