Here's an idea: Let the business owners and ordinary citizens buy handguns to defend themselves like most of the rest of the country, without any restrictions more than the usual NICS checks and other rules and regulations that the rest of the state must follow. Also, allowing law-abiding citizens to carry concealed with a permit that's issued to anyone that applies and passes a criminal background check will immediately reduce the crime rate.

All these big cities need more law-abiding citizens with guns, not less: Instead, Bloomberg has inherited 8.2 million subjects, which ~45,000 cops must control. They can't be everywhere at once, and when seconds count, they're only minutes away.