Indeed. I am not sure if everyone realizes this, but weapons of this class are already capable of taking out subsonic cruise missiles. For harder or faster targets, multiple beams can be aimed at the same spot on the target. Rheinmetall demonstrated this capability 8 years ago when they shone five 10kW laser beams at the same target simultaneously.
If you scroll to 6m15s point of this video, you can see how such a technique would work out against cruise missiles:
EDIT:
This will be hugely disruptive to nations who don’t have an adequate counter-measure in development. We are on the cusp of a major paradigm change. The USN LCS Little Rock will be fielding a 150kW Lockheed Martin laser on its next deployment.
Maybe I am missing something here, but this seems way more complex, expensive, and possibly less effective than conventional guns... at least at this time.