In January 1950, US Secretary of State Dean Acheson drew a line stretching from Alaska to Japan to the Philippines. This new defensive perimeter announced a radical shift in how the United States understood its own security. Seven decades later, that line and the arc of islands running along the western Pacific that strategists call the first island chain has become the most dangerous frontier on Earth.

In The Perimeter, James Crabtree travels its entire length - from the vast bases of Hawaii and Guam to sleepy Kinmen Island caught between China and Taiwan - interviewing generals, diplomats and strategists on both sides of the contest. As China's military modernizes at breathtaking speed and Beijing moves to challenge American dominance in Asia, Crabtree answers a question with consequences that will be felt far beyond the Pacific: is America ready?

Urgent and authoritative, The Perimeter is the essential guide to the defining geopolitical contest of our time.