President Donald Trump’s trade and foreign policies are shaking up the U.S.-dominated post-Cold War order. That troubles many allies, who worry that their economies will suffer as America withdraws from its security guarantees.

There’s one way, however, for these innovations to reassure allies on both counts: using the promised new investment in the United States from Trump’s trade deals to increase America’s defense industrial base. The details of the trade deals with Japan and South Korea are an excellent example of how this can work to increase America’s naval capacity dramatically.