Chaos predicted by proponents of UNCLOS if the U.S. didn't sign has not appeared in last few decades

Critics of the U.S. refusal to sign in 1982  predicted ocean chaos, but as noted earlier, not once has an American ship been denied passage. No country has had either the incentive or the ability to interfere with U.S. ship- ping, and, if one or more had, the LOST would have been of little help. In 1998 treaty supporters agitated for immediate ratification because several special exemptions for the United States were set to expire. Washington did not ratify and no one seemed to notice.

Ironically, problems cited by U.S. shippers -- creation of a “particularly sensitive sea area” off of Europe, for instance—have involved alleged misinterpretations of the treaty, not America’s lack of membership.⁶⁷ And foreign shippers have attempted to use the LOST to escape application of U.S. environmental controls.⁶⁸ Joining the treaty would provide no panacea.