We could have had healthcare.
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".
The United States military budget is now 1.5 trillion dollars per year.
We wouldn't need healthcare.
We'd just be dead.
We absolutely can, and will, go get those asteroids.
That's not the case. If the USA had a more functioning political system (ranked choice voting etc) and didn't hate 'communism' so much then they would have healthcare.
See also: not having daily mass shootings.