The US spends over 50% of the defense spending of the entire world.
The US + Europe + Japan + Canada + Australia + India spends on the order of 85% of the world’s defense budget.
Its higly probable that continuing to occupy S. Korea, Japan, Germany, Italy, etc. are not “vital” to American national security. Global American security through the use forward projection of power on existing American possessions only, especially Guam and Diego Garcia, would be immensely cheaper than the current deployment of forces, and would force a rethinking of the purposes of those forces and their size.
While I think troops could be withdrawn from a number of spots, that’s not the budget issue and you know it. Nowhere close. “Entitlement” spending, Social Security, Medicare, and other idiocies are the central problem, and it doesn’t matter if taxes are “historically low,” they are ridiculously HIGH for the current business climate. I repeat, there is NEVER a time not to cut taxes.