Maybe for subsonic, high end missiles I'm extremely skeptical. Need 5-10MW to get useful dwell power on high end hypersonic inherently shielded against reentry thermals. Speculative laser defense are infra size defense, not mobile trailer size. Factor in duty cycles (i.e. shots per minute) and it seems dead end. Half of economics of missile defense is mobility - building density relative to threats by moving platforms. Last 2 parts real constraints, high-end adversaries coordinate salvos to arrive in time. Interceptor magazine depth limited = still throw 100s of interceptors to engage multiple targets if required. Lasers = serial visual range engagement. Figure out dwell time + duty cycle to saturate. Hypersonic can go from over horizonal to hit target in 10 seconds, a laser couldn't engage more than 1-2 missiles in that time. Technically 1, because by the time you fried 1st target the 2nd is so close the shrapnel will hit on momentum.