A lot of Polk answers. I feel like an idiot that I don't immediately know what that would be. Can someone provide the bullet point highlights for Polk?
Polk promised, to do four things while President – establish an independent treasury system, reduce tariffs, solve the Oregon territory and get California and New Mexico from Mexico. He also promised not to run for a second term. He accomplished it all.
The Treaty of Guadalupe Hidalgo was a massive win for Polk. It finally gave America total control over basically all of the west from Mexico and had included in it any Mexican claims to Texas. He tried to buy Cuba from Spain too but they didn’t want to lose their rum and sugar just yet. Beyond Mexico, Polk ran such a smooth government that there really weren’t any other crisis’ to deal with. There were grumblings about war in Oregon when England wouldn’t budge in negotiations but Polk handled that matter masterfully and war wasn’t necessary. He got a treasury and reduced tariffs. The economy started to rebound while he was in office and the acquisition of all Mexican claimed lands in the west plus the agreement to take over the Oregon territory once and for all cemented a long standing and growing economic boon for settlers in the west and with it the expansion of the country. He averted any attempt at war with England and got Oregon along the border he originally wanted. He destroyed Mexico and ended up getting the rest of the west along with Texas once and for all. His foreign policy was as close to perfect as you could get. He also set the groundwork for what would become the Panama Canal.
Congress worked well with him. A young House Member named Abraham Lincoln fought him occasionally though. That guy. He politically managed to connect the Oregon problem with the Texas/Mexico problem so that slave and free states were appeased. And instead of continued fighting in Congress over interior improvements that always seemed to favor certain districts over others, Polk got a bill passed that created the Department of the Interior. Overall, he was the one that finished creating the map that was to be the continental United States.