United States: Are there perceived drawbacks to the use of ultra-expansionary fiscal and monetary policies?

With the goal of accelerating the return to full employment, the United States has opted for a long period of highly expansionary fiscal and monetary policies. What are the possible drawbacks of this choice, as perceived in the United States and in reality? The appearance of asset price bubbles and a further rise in wealth inequality. This drawback, although serious, is probably not felt very strongly in the United States. The appearance of inflation. But as long as there is underemployment, this remains unlikely. External deficits, the accumulation of external debt and, as a result, the risk of a depreciation of the dollar’s exchange rate. But this is a problem for the rest of the world and not for the United States. The irreversibility of the expansionary monetary policy, due to the very high public debt ratio. But the Federal Reserve does not seem overly bothered by this. Ultimately, there are few perceived barriers in the United States to the sustained use of ultra-expansionary economic policies, even though the dangers of this choice are real.