There are only two ways to decrease the deficit and debt--increase revenues or decrease expenditures. And expenditures can be further divided between defense/national security and social welfare. Let's look at each:
Increasing revenues tends to come across as increasing taxes, specifically increasing tax rates, which is unfortunate because there are other and better ways. To understand the picture better, let's compare USA tax rates to those in the Nordic countries (Sweden, Norway, Finland. Some results may surprise you (USA rates include average state taxes).
Total tax bite out of GDP: Nordic 41.9%, USA 25.0%
Top individual income tax rate: Nordic 43.6%, USA 41.7%
Top rate kicks in at: Nordic 1.4 times average income, USA 8.5 times average income
Average wage earner income tax rate: Nordic 21.9%, USA 11.7%
Top corporate income tax rate: Nordic 20.9%, USA 25.8%
Sales/consumption tax rate: Nordic 24.6%, USA 6.0%
(Source: OECD Tax Database, online at
https://www.oecd.org/tax/tax-policy/tax-database/)
Clearly, the Nordic systems generate far greater tax revenues (as a % of GDP) than the USA system, but not really by taxing the rich and definitely not by taxing corporations. They generate greater revenues from two sources that primarily hit the average person--income taxes and consumption taxes. It's an everybody pays and everybody benefits system (most social programs are not means-tested). By the way, the Nordic tax approach--lower, flatter, and broader (larger tax base)--is exactly what both the Bowles-Simpson and Domenici-Rivlin groups recommended over a decade ago when looking at reducing the deficit and debt.
Decreasing social expenditures: Because the Nordics are everybody pays/everybody benefits, they do not require the legion of bureaucrats to perform the gatekeeping function, and therefore their administrative costs are substantially less. For example, France can provide Bismarck-funded care to 99.9% of its population for less per capita than the USA spends not to provide universal care. Same on the welfare side, where a subsistence-level universal basic income (UBI) can cost less than the hodge-podge of focused and means-tested income redistribution programs.
Decreasing defense spending: Here the problem is a bit trickier because there is an obvious need to maintain a capable force, else none of the other stuff matters. USA defense spending currently goes 14% ($100B out of a $700B defense budget) to combat, 9% ($60B) to combat support, and 77% ($540B) to admin/overhead. You could add 50% to combat and combat support and cut 25% from admin/overhead to produce far greater defense capability while generating a $50B reduction in overall defense spending. Reforming procurement could also help. The Navy, for example, is spending about $15B apiece on the Ford class carriers (versus $9B for the preceding Nimitz class), and so far the cats, traps, weapons lifts--and toilets--are not performing up to par. The Navy is obsessed with high-dollar, high (and untested) tech, cutting-edge acquisitions, when some gaping holes in capability could be addressed far more cheaply--anti-submarine warfare (ASW), naval gunfire support (NGFS), and mine warfare. Finally, 400K active duty shots with 1MM reserve sots for half the cost, while increasing end strength by 600K. By the way, that is how Israel, Switzerland, and Sweden manage to punch above their weights--and how Russia and China do it, for that matter.
So there are ways to cut fat while actually increasing muscle.