Comment by pjc50

Combined arms is the probable solution for a Ukraine type war. As soon as your expensive laser lights up, it's got a couple of minutes to move before artillery shells arrive.

Of course deeper into Russia that's safe .. but instead you have the problem of a huge area to cover. You can protect a few high value targets but not everywhere. Consider something like the early stages of the Iraq war: target every single civilian electrical substation and petrol station with a drone bombing.