The very nature of a terrorist operation requires a small number of attackers, usually one or two, operating against the target location or person.
Given the degree of training and equipment complexity required to put a single AT missile on a tank in an open battlefield, the requirements for a civil police aircraft to be able to safely and accurately oppose one or two (probably unidentified) terrorists in a populated urban area have to be beyond any reasonable consideration.
Additionally given the nature of popularity politics, I seriously doubt if any senior police officer or relevent government official would want to risk their career on the thought of mission failure or collateral damage/casualties.
But that's just my opinion
