Reagan’s election in 1980 brought a bunch of these Democrat, neocon defense hawks into the GOP including the likes of Ben Wattenberg and Jeane Kirkpatrick. Unfortunately, they’re the ones who’ve controlled the foreign policy and national defense apparatus for almost forty years. Definitely the CFR crowd.
Trump will fare better by not having Kagan's support--as must be evident from Kagan's praise for recent American foreign policy. The Neocons in the Bush Administration bear a considerable part of the blame for what almost destroyed the Republican Party.