Framing your disagreement with the Ukraine conflict in money terms ("we can't afford it, the debt/interest is too high, we must raise taxes, etc") is incorrect.
The US can always afford anything denominated is dollars (including people, who are paid wages), if those things exist or projects can be implemented to create them. Reallocation of those resources may mean the gov pays above the going rate paid by the private sector, which you experience as inflation. Bonds and taxation are not required--war bonds, for example, are a method to remove the public from competing with the gov for real resources. The cash you would otherwise spend is removed from your account and you get a bond which you can't use to purchase anything. The gov doesn't want your money, it want to stop your spending temporarily. It's a way to drain money from the economy.
If you disagree with the conflict, frame your arguments in real terms. You think the conflict is wrong because X, Y or Z. But saying we can't afford it is simply wrong.
The implications for all other gov spending on programs and projects, the CBO, everything anyone says about the budget, should be obvious. It's all just politics.
Boomers struggle with this, because they lived under a gold standard which no longer exists. Boomers cannot comprehend economic systems without fixed exchange rates. Unfortunately.