Earlier quoted context omitted.
US healthcare costs on the order of $3T per year. The Iraq war cost about $2T over a decade. You could have about 10% subsidized healthcare, which I would obviously argue is better than pointless war killing tons of people. But you couldn't just "have healthcare".
I don't think OP is talking about a specific war, but the overall cost to maintain such a capability and project force all over the world. At least that is what I perceive when people lament about lack of healthcare. The United States military budget is now 1.5 trillion dollars per year.
We wouldn't need healthcare.
We'd just be dead.