You guys are missing the point: It's NOT a binary choice, not either/or. We can afford both, it's strictly a matter of political will.
The only things stopping us are the neanderthal debt-hawks who can't stand the idea of government helping anybody. The fools that think we have to balance the budget. A nation that can create its own currency at will and is the only source of that currency is not subject to the same accounting principles as a household.
Since Nixon abrogated Bretton Woods in '72, the US--unlike the Euro nations--has been entirely monetarily sovereign. We can create dollars at will. As Satan Alan Greenspan once put it "The United States can pay any debt because we can always print money to do that."
There is nothing to stop us from buying as many Patriot missiles, supercarriers and nuclear ballistic missile subs as we think we need to enforce Pax Americana.
You may recall the world-wide unpleasantness in the first half of the last century. Since we've been enforcing the peace with missiles and ICBMs and suchlike, there has not been a repeat of that nastiness.
Pax Americana has worked, is working now and will work for the foreseeable future because the alternative is madness.
And remember, all those subs and missiles and supercarriers, they're made in the USA by us. And after we work at the shipyard or missile factory, we go home and buy cars and TVs and cellphones and Big Macs and all the rest of it.
All we need are politicians with enough sense--and enough courage--to recognize the new economic reality.
If you want to understand this stuff, read up on MMT--Modern Monetary Theory.