The United States should not have embargoed Japan. The United stars should not have been involved in any of the world wars. Sweden has been neutral in all conflicts since 1814 and that has worked out quite well for them.
If the USA hadnt gotten involved in the European theater of WW2, and invested the required resources in the Manhattan project, its very likely that the Nazis would have gotten the bomb first and used it to beat the red army. This would have allowed Hitler to consolidate power throughout the continent before eventually invading England. Although Im a stanch opponent of the modern military adventurism of recent administrations, getting involved to cut down the rise of Hilters power was a huge positive for generations of Europeans (and probably the rest of the world).
