A missing Panama isthmus and access to Central America

What might change if the Panama isthmus disappeared in 1450?

The proposed effects are changed Caribbean conditions and easier naval access to Central America from both oceans, altering later strategic calculations.

Removing the Panama isthmus in 1450 creates an imagined sea passage with consequences for both local conditions and later strategic geography. Stronger currents and storms in the Caribbean are among the proposed effects. Ships could approach southern Mexico and Central America from both sides instead of armies having to cross a large land barrier to reach them. This opens another possible route for later American expansion in the scenario. The explanation depends on the invented geography rather than projecting that outcome onto the real region.