General Discussion

I mentioned the driving distance from Key West to Pensacola because it show the actual coastline has to be shorter than that distance.

The numbers I provided are a fact. Why you refuse to acknowledge them as such is a mystery to me. They are 100% True. Mexico's coastline is 1743 miles and the US only 1700. From wikipedia:

https://en.wikipedia.org/wiki/Gulf_of_Mexico

Geography
The Gulf of Mexico's eastern, northern, and northwestern shores lie along the US states of Florida, Alabama, Mississippi, Louisiana, and Texas. The US portion of the coastline spans 2,700 km (1,700 miles), receiving water from 33 major rivers that drain 31 states and 2 Canadian provinces.[25] The southwestern and southern shores lie along the Mexican states of Tamaulipas, Veracruz, Tabasco, Campeche, Yucatán, and the northernmost tip of Quintana Roo. The Mexican coastline spans 2,805 km (1,743 miles). On its southeast quadrant, the gulf is bordered by Cuba. It supports major American, Mexican, and Cuban fishing industries. The outer margins of the wide continental shelves of Yucatán and Florida receive cooler, nutrient-enriched waters from the deep by a process known as upwelling, which stimulates plankton growth in the euphotic zone. This attracts fish, shrimp, and squid.[26] River drainage and atmospheric fallout from industrial coastal cities also provide nutrients to the coastal zone.

A piece of advice - quit trying to argue this. you are wrong.