You could fix infrastructure by slashing the US military down to a reasonable size (~2.5% of GDP), there are no other large problems you can fix with that money. The scale of the entitlement problem, healthcare cost problem, etc. is far beyond anything that $150b-$200b per year will solve long-term.

I have no interest in seeing Chicago fix its pension problems by using funding taken from the US military. Chicago made its bed by intentionally, dramatically over-promising, it gets to sleep in that bed. National high speed rail? That would get my vote, so to speak.

We could throw some money at the university cost problem. However that's not lacking funding at all. In fact it has far too much funding, we need to deprive it of the federal slush money and legally mandate how funds can be spent (ie restrict admin spending). It's a massive theft cartel run by the admins at the universities, they're the ones that have universally benefitted by perpetually raising the cost. You can see that represented in the charts comparing the extreme expansion of admin cost & employment at universities, vs the employment of eg professors, over 30 years.