How do you weaponise a Xenomorph anyway?

So I was listening to the cracked podcast and they made a point that I've wondered about now and again.

In Alien, we are told that the company "must have wanted the Alien for the weapons division." In Aliens, Burke states "Those two specimens are worth millions to the bio-weapons division!"

But... how? What would you do with a Xenomorph to make it a weapon? How would you make millions off of using it as a weapon?

Is the idea that you drop eggs into enemy territory like a bomb, and then wait for the Xenos to facehugger your enemies, producing a Queen and then building their numbers until they annihilate the enemy? Because that's just idiotic if you think about it for even a second. Imagine the Allies deciding not to do D Day, and instead dropping eggs into Germany. A year later, sixty million Germans are dead! And now we have a country with sixty million Xenomorphs in it instead. Um.... yay? This is helpful how, exactly?

Well okay, but it's space! You can drop them onto enemy planets and wipe out everything!

Okay, but... how is that better than just nuking the enemy planet instead? Bearing in mind that very few nuclear weapons escape captivity and start reproducing and swarming over their creators...

And of course, this all gets worse when we discover in Prometheus that the Xenomorphs were invented as weapons in the first place. Dumb, dumb, dumb.