Dear minions,
You need to build a giant stratosphere laser mounted on a hot air balloon.
I know, I know, it sounds way cooler to have a giant space laser circling the planet from a satellite or to have a moon base with a giant laser. People take you a lot more seriously when you send threatening Youtube videos and you have a moon base.
Look, a moon base is great. It's nice to have lofty goals. But start with a hot air balloon and work your way up. It's affordable and can still shoot lasers. The only downside is everyone will laugh at you.
... but you'll be the last one laughing. Assuming you don't crash into the ocean or get shot down by sharks with lasers attached to their frickin' heads.
mwahaha!!