Solar is great, but ...
It's not quite there yet. In fact, it will never be there until we can create an
efficient way of storing and releasing the excess generated. Solar from
space is frankly insanely dangerous. If you want to get the energy HERE,
you need to either bounce it via a mirror (safe as regular sunlight for the
most part, but inefficient) or you need to convert it into microwaves.
Imagine a satellite in orbit that can "power" an earth station being taken
over and aimed at a city. Nasty.
The problems we face are not so much the war for energy, its a war over ideologies/faiths. You have a virulent form of Islam that is not content to
wait to convert people to it's faith. Granted, much of the terror is fueled
by money earned by selling oil, but it would still exist regardless.