The USAF is acutely aware of the risk, and there are already policies in place, according to articles I read a few years ago, limiting usage of the anti-ballist

The USAF is acutely aware of the risk, and there are already policies in place, according to articles I read a few years ago, limiting usage of the anti-ballistic missile defenses for this reason. For example if North Korea launches a missile at the US, they will only attempt to intercept it using anti ballistic missile interceptors based in Alaska. Launching from ABM sites in the lower 48 at a target coming from the DPRK would result in interceptor trajectories crossing China, and no one wants to take that risk (the launch of an ABM interceptor looks a hell of a lot like the launch of an ICBM).