Correction

Writing yesterday, I noted there are few U.S. flagged ships, which is largely true with a major exception I forgot to mention. Ships carrying cargo for the U.S. military are required by Congress to be U.S. flagged. We taxpayers pay more to move military goods so Congress can subsidize U.S. seafarers' unions.

See the Associated Press story at RealClearDefense. The important part of this story, almost glossed over in the general narrative, is the second half of this sentence.

The U.S. Navy has accompanied four American-flagged ships moving through the Strait of Hormuz at the mouth of the Persian Gulf, and may expand that aid to other nations to ensure they get no interference from Iranian vessels.

If the U.S. starts protecting all, or most, transiting vessels the risk of an armed confrontation between U.S. and Iranian navy ships increases in the narrow Strait of Hormuz.