They're not cutting the budget, just rearranging spending priorities (i.e., more to the border -- as if that is where our biggest military threat will come from).
In fact, the upcoming Budget calls for an _increase_ in the defense budget.
One thing to keep in mind that Federal Spending represented 23.4% of GDP in 2024. Around 12% of that is defense spending. I have yet to see any way these cuts do not result is massive decreases in GDP. Even if all of it is redirected to defense.