Watch the US Navy's laser weapon in action - CNN Video

So the open question I have.........do they need a Nuclear reactor to power it?

Set Phasers on stun... (Yes, we our living our science fiction, maybe even beyond what the most creative people have imagined)

This is actually a good fit. Ships are better for generating power for something like this with current technology. If this were to a be a ground based weapon capable of taking on ground based armor, it would have to be a power source the size of a washing machine and a weapons the size of a 120mm tank main gun.

They are tinkering with a Stryker based laser for anti-aircraft use. I worry that nations will further develop blinding weapons.