Last October, thousands of American and Japanese troops and hundreds of naval vessels from both countries held a joint landing exercise not far from Okinawa. In recent years the annual operation, Keen Sword, has become more intense and more extensive. This time, an American Nimitz-class aircraft carrier with a strike group participated. Keen Sword is part of naval preparedness operations under “The Quad,” an informal—but growing into a stable—mini-alliance of the United States, India, Japan and Australia. It was formed to counter growing Chinese naval threats to countries on the East China Sea and the South China Sea, and China’s efforts to expand its influence to island nations scattered from the Indian Ocean to the central Pacific. The United States and Australia have long had mutu...

In late April, the Russian military carried out a joint exercise on Franz Josef Land in the High Arctic that began with a parachute drop from an IL-76 transport aircraft at 30,000 feet. The weather at that time of year is still very cold. And yet the Russian paratroopers were able to land and occupy a small island in a three-day mock battle. The exercise was only another manifestation of Russia’s growing military power in the Far North. Old Soviet bases are being refurbished and new ones established. Cold-weather equipment is being developed and deployed. With the largest icebreaking fleet by far, Russia continues to build new icebreakers, including heavy nuclear-powered ships.  Russia’s ambitions are simple: it aims to dominate the High Arctic—including the Arctic Ocean—with a major m...