The opposition against spending in itself is a subset of a wider issue of spending well beyond our means - taking on ever mounting debt. This [1] is a graph of the US debt to GDP. That's a rather unpleasant graph. The countries with comparable debt:GDP ratios (2 worse, 2 better) are Bahrain, Maldives, Laos, and Cape Verde. [2] In fact we have the 7th worst debt:GDP ratio in the world.
So the obvious response here should be - who cares? Nothing apocalyptic's happened so far. True. And the reason for that is because the US has (and to a lesser degree) retains a unique superpower to export our inflation [3] to other countries. This was because of a perfect storm of a number of factors including:
- the USD being world reserve currency (the currency other countries kept under their bed in case of a rainy day, or if they wanted to buy oil...),
- the US being the largest consumer economy
- the USD being the standard in global trade
But these factors are all coming to an end, some slowly and some not so slowly. The petrodollar is basically dead, countries are gradually to detaching themselves from the dollar, an increasing chunk of the largest economies in the world are now no longer settling trades in the USD, and so on. The world becoming more multipolar, the introduction of alternative global currencies, and such will only accelerate this trend. This is also happening that the US economy is starting to slow down.
So basically this level of debt spending is simply unsustainable. If the spending is indeed necessary, then our economy will have found itself in a situation where it can't sustain itself, and there will end up being a 'correction' that'd be far more painful than some bluntly targeted cuts.
[1] - https://fred.stlouisfed.org/series/GFDEGDQ188S
[2] - https://en.wikipedia.org/wiki/List_of_countries_by_governmen...
[3] - https://search.brave.com/search?q=exporting+inflation