The problem is that the population of the US is itself polarized, and different factions want the government to be doing extremely different things with its fun

The problem is that the population of the US is itself polarized, and different factions want the government to be doing extremely different things with its funds. If faction A has successfully gotten the US federal government to fund something for a long time, and faction B hates that thing, campaigns on ending the funding, and then does end it once they win an election and take power - then a demand for the US to not play gotcha games with its funding is isomorphic to a demand from political faction A to keep some of their preferred policies in place even though they are not currently in a position of electoral power.