The “means” of grand strategy are similarly enduring over time. Its basic components include fostering strong alliances and bilateral security arrangements; maintaining a strong and survivable nuclear deterrent; fielding balanced, powerful, and capable military forces, dominant in each warfighting domain, that can project and sustain military power globally and prevail in armed conflict; and providing intelligence services that can ensure global situational awareness and provide strategic early warning.

First, it is important not to confuse enduring, core strategic interests with others that are less central. The current security environment, described in the 2014 Quadrennial Defense Review as “rapidly changing,” “volatile,” “unpredictable,” and “in some cases more threatening” is certainly all those. Yet addressing this environment in fact aligns comfortably with American grand strategy over time.

The new century would transform American grand strategy in different but comparable ways. By a wide margin, the 20th century would prove to be the most catastrophic in history. The Spanish-American War, while revealing many shortcomings in organization and supply for the land forces, showcased a powerful and competent Navy with global reach and made the United States an imperial power with newly won possessions in the Caribbean (Puerto Rico) and the Pacific (the Philippines and Guam).