Created Saturday 21 July 2018
For energy weapons, it's less punching through material as much as trying to be a long enough wave length to not be affected by materials. Reading a bit online (as I guess I should...) shows that really high frequency waves also aren't absorbed since it's not so much the size of a wave being long or short but it's correspondance to atoms' sizes. But--again--with higher frequencies/energies you get other problems, like ionizing/plasmasizing.)
O.K., apparently I've got to look more into this:
A good conductor will not allow radiation to pass through, but at a high enough frequency, the surface of the conductor looks similar to a plasma, and the electrons will not be able to oscillate fast enough to cancel out the incident waves. And thus, the radiation can pass through. (Reference https://www.physicsforums.com/threads/wavelength-and-penetration.350432/)