The U.S. will have no reliable friends or allies and will have to depend entirely on its own strength to survive and prosper.

This will require more military spending, not less, because the open access to overseas resources, markets, and strategic bases that Americans have enjoyed will no longer come as a benefit of the country’s alliances. Instead, they will have to be contested and defended against other great powers. Americans are neither materially nor psychologically ready for this future.

-Robert Kagan