75th Anniversary of D-Day: An Important Reminder About the Wars of Tomorrow

D-Day landings / Getty

"Soldiers, sailors, and airmen of the Allied Expeditionary Force: You are about to embark upon the great crusade, toward which we have striven these many months." So began General Dwight D. Eisenhower, who, on the morning of June 6, 1944, described to American and Allied soldiers what was at stake that day. "The eyes of the world are upon you. The hopes and prayers of liberty-loving people everywhere march with you … you will bring about the destruction of the German war machine, the elimination of Nazi tyranny over oppressed peoples of Europe, and security for ourselves in a free world." The Allies were about to storm the beaches of Normandy, France, launching an operation to enter—not "invade," which implies the Nazis had legitimacy controlling the continent—German-occupied Western Europe. Seventy-five years ago today, the ultimate liberation began.

On the 75th anniversary of D-Day, one can devote countless pages to any number of topics, from the bravery of the Allied soldiers to how the Battle of Normandy changed World War II. All of these endeavors are worthwhile and important, but there is another way to think about the airborne and amphibious landings at Normandy, one that connects that bloody day to the most significant potential wars of tomorrow.

D-Day was the greatest counteroffensive in history. A counteroffensive is, in the broadest terms, a military attack, often on a large scale, launched in response to an attack by the enemy to counter what that enemy has achieved. In World War II, the Nazis overran much of Europe during the early years of conflict, forcing the Allies either to accept this new reality or to challenge it. Challenging the Nazis' gains would mean launching a massive counteroffensive to liberate Europe, hence Operation Neptune (the landings, or D-Day) and Operation Overlord (the larger battle of Normandy). It would also mean an untold number of casualties. Indeed, on D-Day alone, 4,414 Allied troops were killed, including 2,501 Americans, and many more were wounded.

What if the United States had to launch a large-scale counteroffensive today? Would Washington do it? These questions may seem far-fetched, even fantastical, but they directly concern the future of American warfare. Indeed, the American people and their leaders really need to think about the answers, which could have significant impact on Washington's posture toward China and Russia.

In its national security and national defense strategies, the Trump administration proclaims the return of competition between great powers, states with the ability to wield influence on a global scale. Specifically, the administration focuses on China and Russia, both of which "want to shape a world antithetical to U.S. values and interests" that is "consistent with their authoritarian model—gaining veto authority over other nations' economic, diplomatic, and security decisions." The Pentagon has embraced this strategic shift, moving resources from the Middle East to better prepare for competition, and potential conflict, with Russia and, more importantly, China.

The United States still maintains global military supremacy—albeit by a smaller margin than in recent decades—but it could still lose wars against China and Russia, both of which have developed concepts of defeating a more powerful America—and its allies—in armed conflict. I have described these "theories of victory" in previous articles and will not go into full detail here, except for their initial, most important phase, which directly concerns counteroffensives. As I explained in March:

If China or Russia thinks that war may break out with the United States, they will act first and quickly, creating a fait accompli, in this context a new geopolitical situation before American forces can stop them. For example, if it looks like there will be a war over Taiwan, China will immediately seize the island and present the United States with an unpleasant choice: either accept this new reality, or launch a bloody counteroffensive to reverse it. And China will make clear that such a counteroffensive will impose terrible costs: thousands of Americans will die, far more dollars will be spent, and the conflict will only escalate from there. Moreover, such a campaign will be quite difficult to wage because of geography: it is much easier for Chinese forces to defend nearby Taiwan than it is for American forces to re-take an island many miles away. In the case of Russia, this scenario will likely involve the Russians quickly seizing one of the Baltic states in eastern Europe, or even all of them. Again, the choice for Washington is the same: accept the new situation, or wage a war.

China and Russia would hope the United States yields, thus winning a war without even fighting the Americans. Indeed, America's two most powerful adversaries are banking on Washington's unwillingness to launch such a counteroffensive because of an asymmetry of stakes. In other words, Beijing and Moscow believe that Washington would have important interests at stake, but not ones as important as those that they have at stake.

I have argued previously that the United States should launch counteroffensives in these scenarios to protect vital interests, but that is not the point here, on the 75th anniversary of D-Day. Rather, the point is to prevent these faits accomplis from happening in the first place, through deterrence and constant vigilance. Imagine if the West did not try to appease Hitler in the late 1930s and took the German threat seriously before history's greatest monster became strong enough to earn that title and terrorize Europe. Imagine if the West showed a willingness to use force in 1936 or 1938, rearming its militaries and making clear that imperial aggression is unacceptable. Maybe there never would have been a war. Or maybe there would have been conflict, but it would have been a hell of a lot less violent than what ultimately unfolded. Preserving the peace, wrote the great historian Donald Kagan, "requires active effort, planning, the expenditure of resources, and sacrifice, just as war does." History shows that peace only comes through great powers—the United States today—being eternally vigilant and maintaining strong militaries, which they are willing to use when necessary. The trouble begins when an adversary, usually a weaker one, senses weakness or an unwillingness to fight. The United States must understand this fact and adjust its posture accordingly to prevent the aforementioned situations with China and Russia from happening in the first place.

The 75th anniversary of D-Day is an important reminder of what can happen when deterrence breaks down, and of the level of violence that a counteroffensive can entail. The best option, then, is to do everything to prevent tensions from ever reaching that point. After all, while we honor and celebrate the heroes who fought on that day of days, ultimately, we would rather not have to do so, for the goal should be to preserve the peace rather than to wage war. And that means deterrence and eternal vigilance, showing enemies a willingness to fight, hoping that day never comes.