Is there a risk that no one will want to hold US external debt?

The United States has for a long time had a structural external deficit that has led to the accumulation of large external debt . This situation will now get worse as a result of the implementation of an expansionary fiscal policy at full employment. The major risk for the United States is therefore that investors in the rest of the world no longer will want to buy or hold its external debt. If this risk materialised, the United States would have no other choice than to use "international seigniorage", i.e. to weaken the dollar's exchange rate, in order to reduce the weight of the debt. Is it possible that no one will want to hold US external debt ? For this to happen, there would have to be an alternative to investments in dollars . However , the size of financial assets in (Chinese) renminbi is small, euro-zone financial markets are segmented and the euro zone’s situation can give cause for concern, and the difficult situation of some emerging countries may discourage capital flows from the United States to emerging countries. If demand for US external debt nevertheless falls, the United States’ situation would be serious given its continuous need for external financing, amplified by Donald Trump’s policy.