The correct answer for the first blank is Irreconcilables.
The correct answer for the second blank is Reservationists.
The League of Nations was president Woodrow Wilson's plan that would help keep peace after World War I. Ultimately, this would be an organization made up of several different countries who would work together to keep international peace. However, many Congress people disagreed with joining this organization. The main argument around not wanting to join was based on the fact that this League of Nations would result in the United States getting involved in foreign affairs that they have no business being a part of. These two aforementioned groups end up winning this battle, as the United States never joins the League of Nations.