> At some point we should outsource our armies and perhaps even governments.

Funnily enough, this was how war functioned in Europe between 1500-1750s. Armies were too expensive to maintain, so states hired mercenaries. The problem was that mercenaries wouldn't have any incentive to risk themselves to end things quickly. And when you inevitably run out of money to pay them, in the best case they'd just pack up and leave. In the worst case, they'd loot your city on the way out.

Source: https://press.princeton.edu/books/paperback/9780691027647/ma...