Getting enough energy on target isn’t always the hard part of the challenge. Rather, integrating a system that can detect, classify or ID (depending on ROEs), and track - and packaging the power, beam control, and thermal management system into a small, operational, turn-key system - are the hard challenges. Each of the things I listed are still challenging, but everyone focuses (heh) on power on target. The Navy and Army have a reasonable chance of fielding an operational system in the next decade, but IMO the AF has a long way to go. I also get the impression that the AF is investing the least in high energy lasers, but I haven’t seen their budget numbers so I might be wrong. When I worked JSF in the 90s and 00s, they touted putting a laser on the plane but I knew that wasn’t happening for a long time.