With a new US administration under Donald Trump tempted to use military power in ways still hard to predict, it is timely to review the major military challenges for the United States in the Indo-Pacific region. All draw attention to Sino-US relations, from the Korean Peninsula to the Indian Ocean, encompassing both the South China Sea and the East China Sea, where Taiwan is situated. In this introduction we draw together arguments from the four articles in this Special Forum. They range from a proposed strategy to force change in North Korea to a “non-provocative” approach to counter China’s “anti-access, area denial” strategy, to continued caution in not arousing China or India to reconsider long-standing commitments to rather limited deterrence in nuclear arms, to awareness that US policy changes would only have a modest impact on increasingly close Sino-Russian military cooperation. The articles offer new insights into these four challenges facing US military power in the region.