Originally Posted by Snowfire
Please direct your attention to the next generation of US navy destroyers for railguns military usage of railguns today.
As for lasers...the only reason we don't use them is because they suck in anywhere but vacuum due to the sheer amount of power needed to punch a beam that will actually harm its target through the atmospheric interference (Inverse-square sucks).
They're both modern concepts, one of which exists today and the other of which we were capable of twenty/thirty years ago.
We just scale them up - as C'nor says - through the use of a Legendary concept power source. Which is all we really need to get the lasers to work in atmosphere and seriously amp up the power of the railguns.
The physics of weapons in space is a lot more complicated than you make it out to be. Especially if you add all the issues of cooling the ship into the mix.