Climate change is causing drought conditions that are making the Panama Canal harder to operate and more expensive to pass through.

Many assume this Trump tough talk is his signature bluster, which he uses to threaten allies to do what he wants. When he suggested renaming the Gulf of Mexico the “Gulf of America,” Mexican President Claudia Sheinbaum trolled Trump with a 17th-century map labeling the United States “America Mexicana.”

Hern said the president-elect is concerned that China is essentially operating the canal. Observers say climate change is a factor in the canal management dispute and renewed interest in Greenland.

Panama has rejected president-elect’s threats, but Hong Kong and mainland Chinese companies have much at stake.