The 1940's and 1950's reduced it through raising taxes, not cutting social services. There was actually a large expansion of social services and infrastructure projects at the time.
Slash and burn economics/austerity are not the only option.
The reason you saw high spending starting around December 7th 1941, is because that's the day we entered WW2 and started working as the industrial/commercial vessel behind the most expansive war humanity has ever seen.
It plummeted afterwards because of dramatic spending cuts after the war ended in 1945. The budget in 1946 cut discretionary spending (which is what funds the military) by 43% (38.5 billion), and then it was cut another 41% in 1947. Inflation adjusted the spending cut in 1946 was $619 billion.
The 'great expansion' of social services began in the 60s which led (in part, Vietnam and other issues obviously played a huge role) to the US defaulting on its economic obligations under Bretton Woods in 1971, which is when our current economic era of unconstrained completely fiat spending began.
The 1950's expanded social services considerably, including major infrastructure projects like housing and highways. The cost of the GI bill alone after WW2 was $140 billion in today's dollars.
Cutting military spending is an option but doesn't seem to be on the table.
It remains words for now but Trump is now calling for a mutual 50% defense spending cuts amongst Russia, China, and the US - as well as a return to nuclear nonproliferation arguing quite reasonably that we all have enough nukes to destroy the world multiple times over, so what's the point? [1]
It's likely to preempt media attacks claiming Trump is undermining US defense and security by cutting military spending, especially if DOGE manages to find some large areas to cut (one can only imagine the headlines...). It's unclear if they would agree (especially when there's going to be immense distrust), but this sort of rhetoric is the most rational and logical that I've seen in decades.
Having a leader with messianic delusions is not necessarily a bad thing it might seem, at least for now.
[1] - https://fred.stlouisfed.org/series/GFDEGDQ188S