[ChuckMcM]

This is a good point, the weak spot is that the missile designer "knows" where the extra energy is coming from (friction with the air). Once you add a laser, the energy can come from "any" angle (within some limits of course).

Think of it this way, the shuttle could not dissipate massive energy on the 'top' because re-entry involved air over the bottom.

As for power rating, the Boeing High Energy Lasers were demonstrating effective missile defense in 2017[1], they were ramping up their power levels pretty quickly.

I see the biggest impact early on being fleet defense against hyper-sonic anti-ship missiles rather than ABM defense. Basically a CWIS replacement since it doesn't help to lose your $10B aircraft carrier to a $100M missile.

[1] https://www.boeing.com/defense/missile-defense/directed-ener...

[nostrademons]

Warheads spin on re-entry anyway, so laser energy directed at any point other than the centerline (which is pretty hard to hit) will get dissipated and spread across the whole warhead.

I think the biggest impact is actually against low-tech threats: swarms of fast attack suicide boats, or 1960s-era cruise missiles that have ended up on the black market. There's a big cost advantage to being able to take these out with a quick 30kW pulse rather than a million-dollar missile, particularly since the threat itself probably cost less than a million dollars.

In a great-power conflict (where "great-power" is rapidly expanding to include private multinational corporations) the U.S. military is fucked anyway, but then, so is the opposing power. Perhaps that's the best we can hope for, because it's a pretty strong incentive not to start great-power conflicts in the first place.

[Lev1a]

> In a great-power conflict [...] the U.S. military is fucked anyway, but then, so is the opposing power. Perhaps that's the best we can hope for, because it's a pretty strong incentive not to start great-power conflicts in the first place.

Yes. That is indeed the concept of a (nuclear) deterrent.