The arrival of American soldiers gave the a military advantage.

The League was founded in 1920, after World War I, but failed to maintain peace during World War II. ... The League of Nations was thought up by Woodrow Wilson, the American President during the First World War. It was to be a group of nations that worked together to keep peace.

both are true, the congress does have the power to create banks, even if this power is not specifically described in the constitution, since there is nothing restricting it and there is power given to the congress to make "all laws which shall be necessary and proper". maryland was not allowed to tax a branch of the national bank operating there, and the supreme court decided that no state could. both of these topics were discussed in a decision of the mcculloch v. maryland case in 1819.