A decisive Japanese victory at Coral Sea

Would the United States seek peace after a decisive Japanese victory at Coral Sea?

No; it would reinforce the Pacific effort, delay some European operations, and continue fighting despite a longer war.

The United States would commit still more resources to the Pacific, possibly delaying Operation Torch and drawing additional British support eastward. Pearl Harbor and attacks on American territory made a negotiated withdrawal politically untenable. American industry would continue producing the Essex-class carrier force that Japan could not match. The likely effect is therefore a longer and more resource-intensive war rather than a different final outcome.