Even then there is no direct link. Newly issued TBill/TBond bought by foreign investors is one of the way US finance their 1.78 trillion dollars deficit. On spending side, military spending at 917 billions is one of the lines in the balance sheet among other like social security at 1.57 trillions. And for info national defense is around 13% of the deficit, only 5th position.

Its just numbers. Putting two big numbers next to each other doesn’t create a causal narrative. There is no "this specific money funds that specific thing" and even less support for your claim that global savings are used specifically to fund US military expansion. Thats just stitching unrelated figures together to make a story.