You're right, not to finance competitors. There are maybe 3 or 4 companies that matter in defense, each making many billions while others get an order of magnitude less. So, no...there is no funding competitors in defense. There isn't much competition to speak of.
But this is not to say the machines Boeing makes are not amazing.
My comments are from working on military contracts. They're enough to make a reasonable person run for the hills.
That is a billion dollar question: how do you get the military to buy my awesome product. The answer is usually absorb the culture and lower your productivity.