I know they started working on that stuff back in the 80's when I was in the military, I'm sure back then it was in it's infancy.
The gas lasers back then proved too slow, cumbersome, and energy intensive.
The big breakthrough has been solid state or ‘fiber’ lasers with efficient energy consumption and quickly reloadable. Along with AI control, they can acquire and fire on their own.
https://www.janes.com/defence-news/news-detail/israel-tests-groundbreaking-airborne-laser
The first laser weapons test I supported was in 1975, as I recall. They have come a long way in nearly 50 years.