[PJBankard]

The third is that it won't be too long before somebody develops a directed energy weapon, and then all bets are off.

I assume you mean one that is cost-effective and portable. As for being developed we did that during the 80s with SDI.

[USNBandit]

The PTO on the front of the F-35 engine has 29,000 hp available. In the A and C models that isn’t driving a lift fan. That could drive a huge generator.