That would make imports more expensive and exports more competitive. Some pain, given we run a deficit [1]. But $50bn/month adustment in a $30tn economy is 2%. Not fun. But not a "crash."

(There is a genuine argument to be made that American voters have been rejecting dollar hegemony across multiple elections for a couple of decades.)

[1] https://www.bea.gov/data/intl-trade-investment/international...