During Polk's presidency, he decided to accomplish 4 main goals that he set up for himself. His goals was to end the dispute over the Oregon Territory, institute an Independent Treasury, gain California from Mexico, and reduce tariffs. Throughout his presidency, he was able to accomplish all of his goals.
The main reason why the Continental Congress was unable to fix the economic crisis after the American Revolution was because they had no power to tax the states--meaning that they could not repay the nation's war debts.
The main result of the war was two centuries of peace between the United States and Britain. All the causes of the war had disappeared with the end of the war between Britain and France and with the destruction of the power of Indians to block American expansion into the Northwest. (I’m not sure if that is correct hope it helps)