The capital inflows mostly prop up consumption by asset holders. This is trickle-down economics. Most Americans are left behind in this system, and that creates real instability. But again, fascism may keep the lid on this inequality. Asset holders like what they see so far — number go up.
You could argue that the government spending and debt funded by those capital inflows - especially with entitlement spending eating up more and more of the budget - mostly prop up consumption by non-asset-holders.
Asset prices went up with national debt. Dollar debt bonds are collateral for everything. If the government cut and taxed away that deficit — what would private assets be “worth”? You could argue that Mr. Market is a welfare queen. He should very be thankful for entitlements.