Except in a few instances, since World War II no American soldier or sailor has been attacked by enemy air power. Conversely, no enemy soldier orsailor has acted in combat without being attacked or at least threatened by American air power. Aviators have brought the air weapon to bear against enemies while denying them the same prerogative. This is the legacy of the U.S. AirForce, purchased at great cost in both human and material resources.More often than not, aerial pioneers had to fight technological ignorance, bureaucratic opposition, public apathy, and disagreement over purpose.Every step in the evolution of air power led into new and untrodden territory, driven by humanitarian impulses; by the search for higher, faster, and farther flight; or by the conviction that the air way was the best way. Warriors have always coveted the high ground. If technology permitted them to reach it, men, women andan air force held and exploited it-from Thomas Selfridge, first among so many who gave that "last full measure of devotion"; to Women's Airforce Service Pilot Ann Baumgartner, who broke social barriers to become the first Americanwoman to pilot a jet; to Benjamin Davis, who broke racial barriers to become the first African American to command a flying group; to Chuck Yeager, a one-time non-commissioned flight officer who was the first to exceed the speed of sound; to John Levitow, who earned the Medal of Honor by throwing himself over a live flare to save his gunship crew; to John Warden, who began a revolution in air power thought and strategy that was put to spectacular use in the Gulf War.Industrialization has brought total war and air power has brought the means to overfly an enemy's defenses and attack its sources of power directly. Americans have perceived air power from the start as a more efficient means of waging war and as a symbol of the nation's commitment to technology to master challenges, minimize casualties, and defeat adversaries.

Annually, CSIS senior adviser Mark Cancian publishes a series of papers on U.S. military forces—their composition, new initiatives, long-term trends, and challenges. The overall theme of this year’s report is the struggle to align forces and strategy because of budget tradeoffs that even defense buildups must make, unrelenting operational demands that stress forces and prevent force structure reductions, and legacy programs whose smooth operations and strong constituencies inhibit rapid change. This report takes a deeper look at the strategic and budget context, the military services, special operations forces, DOD civilians and contractors, and non-DOD national security organizations in the FY 2020 budget.

CSIS senior adviser Mark Cancian annually produces a series of white papers on U.S. military forces, including their composition, new initiatives, long-term trends, and challenges. This report is a compilation of these papers and takes a deep look at each of the military services, the new Space Force, special operations forces, DOD civilians, and contractors in the FY 2021 budget. This report further includes a foreword regarding how the Biden administration might approach decisions facing the military forces, drawing on insights from the individual chapters.

Global air mobility is an American invention. During the twentieth century, other nations developed capabilities to transport supplies and personnel by air to support deployed military forces. But only the United States mustered the resources and will to create a global transport force and aerial refueling aircraft capable of moving air and ground combat forces of all types to anywhere in the world and supporting them in continuous combat operations. Whether contemplating a bomber campaign or halting another surprise attack, American war planners have depended on transport and tanker aircraft.