KYIV, Ukraine—Disease has affected all of America’s wars. In the American Civil War, arguably the first war of the modern era, twice as many soldiers died from infectious disease as from enemy action. 

In the 1898 Spanish-American War, at least seven U.S. soldiers died from disease for every one who died in combat. 

In World War I, amid the slaughter of trench warfare and introduction of airplanes and tanks in battle, deaths due to disease slightly outpaced American combat fatalities by a ratio of 1.1-to-1.

In fact, it wasn’t until World War II that combat killed more Americans than did infectious disease. By the time of the post-9/11 wars in Iraq and Afghanistan, more American military personnel were dying from suicide than disease. 

Yet, the detrimental impact of a disease on military strength can’t be measured by death toll alone. Diseases also can tie up manpower, steal resources, and incapacitate troops without killing them.

“Wars are won by able-bodied combatants,” wrote historian Vincent J. Cirillo in the academic journal Perspectives in Biology and Medicine. “Disease is the enemy’s ally, because it causes an enormous drain on the military’s resources and affects both strategy and tactics.”

The U.S. isn’t currently embroiled in a conflict anywhere near the scale of the world wars. However, a new era of so-called strategic competition has begun in which the peacetime projection of American military force plays a key role in deterring the nation’s contemporary adversaries—authoritarian countries such as China and Russia. 

Whether by aircraft carrier deployments in the Pacific or military exercises in Europe, America’s military is engaged in a global effort to prevent the next world war from happening.  

Yet, the ongoing coronavirus pandemic has served as a stark reminder that infectious diseases such as COVID-19, even in this age of modern medicine, still can pose a potentially game-changing threat to American military power.

Due to an onboard outbreak of the coronavirus last month, the aircraft carrier USS Theodore Roosevelt—a mantelpiece of U.S. power projection in the Pacific region—effectively had to abort its deployment and dash to Guam to offload its crew. 

Meanwhile, in Europe, the coronavirus outbreak brought to a screeching halt NATO’s dramatically ramped-up military exercise schedule, which was set in motion after Russia’s 2014 invasion of Ukraine. 

Most notably, U.S. European Command significantly pared down what was supposed to be the U.S. military’s biggest exercise in Europe in 25 years.


Called Defender-Europe 20, the training event was slated to comprise some 20,000 U.S. troops and last until May. Instead, because of the pandemic, the Pentagon stopped the movement of U.S. troops to Europe on March 13. 

Ultimately, only 6,000 U.S. military personnel made it to Europe for the exercise. All events linked to Defender-Europe 20 either were modified or canceled.

“Anytime there is a delay in training—for whatever reason, and for however long—it affects performance,” Mark Hertling, former commanding general of U.S. Army Europe, told The Daily Signal.

“Think of a professional baseball club that hasn’t practiced in a month … it’s harder to take the field and have the same kind of flow without conducting training events,” Hertling said. “But that’s countered by the fact that the readiness level of Army training is pretty good, even though it’s something that we always need to maintain.”

The U.S. military says the scaled-down Defender-Europe 20 was still a useful endeavor that demonstrated the ability of the U.S. and NATO to project force and operate together in a crisis. 

Many experts say the exercise wasn’t necessarily a success, but its de facto cancellation also wasn’t a significant blow to the readiness of allied forces to defend Europe.

“The massive downsizing or cancellation of exercises like Defender 20 will certainly have an impact on operational readiness, but it will not significantly weaken NATO’s regional force posture,” said Franz-Stefan Gady, a research fellow for the International Institute for Strategic Studies, a British research group.

A Navy spokesman, speaking to The Daily Signal on background, said other U.S.-led NATO military exercises slated for the coming months—in countries including Estonia and Poland—have not yet been canceled. 

“The pandemic can certainly add obstacles to maintaining interoperability in the short term,” said Eugene Chausovsky, senior Eurasia analyst for Stratfor.

“However, if a true threat were to materialize that rivals or surpasses the current threat of the pandemic, NATO would likely ramp up its activity and respond accordingly,” Chausovsky told The Daily Signal.

‘Not Only Missiles’

About 72,000 U.S. military members and civilian support personnel live and work in Europe, according to U.S. European Command. In place of the Defender-Europe 20 events, it said, U.S. military forces across the Continent “continue to conduct individual and unit-level training, such as gunnery exercises focused on maintaining tactical proficiency.”  

Hertling said smaller-scale, unit-level training exercises could offset some of the impact of Defender-Europe 20’s reduction in size. But, in the end, nothing truly substitutes the need for the kind of real-world practice that such a large-scale, complicated training exercise offers, Hertling added.

After a generational focus on counterinsurgency warfare in the Middle East and Afghanistan, U.S. armed forces are spinning up for a new era of conventional threats from other nations. 

Military exercises such as Defender-Europe 20 are also an invaluable opportunity to practice some of the more banal aspects of waging a war—such as figuring out what roads to take from one place to another, or where the fuel tanks are located at an airfield. 

Thus, some experts say the coronavirus crisis is a lesson learned in how unforeseen crises such as a pandemic can stymie NATO’s ability to move forces around Europe.

“The pandemic shows that not only missiles can hamper military traffic,” a Polish diplomat working at NATO headquarters told The Daily Signal.

Downstream Effects

John Spencer, chair of Urban Warfare Studies with the Modern War Institute at West Point, said early curtailment of Defender-Europe 20 likely won’t impair NATO’s operational, warfighting abilities. Rather, the pandemic’s greatest impact may be on the economic priorities of NATO members. 

“To me, the impact of COVID-19 will be downstream,” Spencer told The Daily Signal. “The global economic bill will come due quickly, and I fear many [NATO countries] will look toward their militaries, a great reduction in military spending, to find money. That could change the conditions for the U.S. and NATO in Europe.”

Spencer added: “Russia has to see this coming and if it makes moves to secure its current military spending and investments, it could gain advantages in the European region.”

Other experts agree, pointing to a post-pandemic economic downturn as the biggest threat to NATO’s military readiness—and an opportunity that Moscow may try to exploit.

“Over the next five years, the economic contraction caused by the COVID-19 outbreak is bound to negatively impact defense NATO budgets,” Gady told The Daily Signal. “Reduced military spending will of course have a negative impact on readiness.”

“If the recession, which is likely to follow, is deep, then NATO will be faced with inevitable cuts to the defense budgets of its allies,” said Marcin Terlikowski, head of the International Security Program at the Polish Institute of International Affairs.

“Cuts will mean less investment into new capabilities, less contribution to crisis management operations outside the transatlantic area, and less exercises at home,” Terlikowski told The Daily Signal. “In the long run, such a situation may have an adverse effect on the credibility of NATO’s defense and deterrence.”

The economic consequences of the COVID-19 pandemic, along with a precipitous drop in global oil prices, have hit the Russian economy hard, too. So, even if NATO countries deprioritize their defense spending, as some have predicted, Russia may not ultimately be in an economic position to take advantage of its newfound edge once the dust settles after the pandemic.

“Such economic weakness will make Moscow less likely to undertake military action unless deemed absolutely necessary by the Kremlin,” Chausovsky said.

As of Monday, Russia has reported 18,328 coronavirus cases and 148 deaths from COVID-19. Nevertheless, a major Russian military exercise called Caucasus 2020 remains scheduled for September. And, despite the pandemic, the May 9 parade in Moscow to celebrate the Soviet victory in World War II is still on the books as well.

Russian formations comprising thousands of troops were filmed recently having parade practices, contradicting a call by the Kremlin for Russian citizens to practice social distancing measures.

“I suspect Russia is also experiencing, or is about to experience, a large-scale readiness issue, especially given their methods of feeding, using barracks, and having mass transports,” Hertling said. “I’d suggest their forces are going to have a significant spread of the disease.”

Reassure and Deter

The Obama administration announced the European Reassurance Initiative, or ERI, in June 2014, months after Russia illegally annexed Ukraine’s Crimean Peninsula and launched military operations in eastern Ukraine. 

The program called for a buildup of U.S. military forces and equipment in Eastern and Central Europe, as well as rotating military exercises throughout the region. 

Totaling roughly $1 billion in 2014, ERI was meant to be a temporary measure to deter Russia from military provocations and show NATO and its European partners that the U.S. was committed to their defense.

Since taking office, the Trump administration has boosted spending for the Obama-era program, now known as the European Deterrence Initiative, underscoring that the Russian threat to NATO and its European partners has not dimmed since 2014. 

With about $6 billion pledged for the program in fiscal year 2020, the number of American troops scheduled to rotate in and out of Europe was set to ratchet up this year.

Exercises such as Defender-Europe 20 are meant to show Moscow that the U.S. is willing and able to defend its European allies by force. However, deterring Russia ultimately depends on much more than military exercises, many experts say.

Since Russia’s 2014 invasions of Ukraine’s Crimean and Donbas territories, NATO has forward deployed rotational forces—known as multinational battlegroups—in the three Baltic countries and Poland, and implemented air policing missions over the Baltic Sea. Those initiatives have not been affected by COVID-19, NATO officials said.

“Conventional deterrence against Russia in Europe remains strong for the time being despite a notable impact on the operational readiness of U.S. and NATO forces globally as a result of the COVID-19 outbreak,” Gady told The Daily Signal.

Operation Atlantic Resolve, which falls under the European Deterrence Initiative funding umbrella, comprises a broad gamut of exercises and temporary deployments of U.S. military hardware and personnel throughout the Continent. 

As part of Atlantic Resolve, approximately 6,000 U.S. soldiers are, at any given time, in Europe conducting operations and exercises across 17 countries.

America’s more prominent military presence arguably has played a pivotal role in deterring Russia from overreaching and starting a regional conflagration after its 2014 invasion of Ukraine.

Still, Eastern Europe remains a region on edge.

In December, Moscow announced that it was deploying additional troops to its Kaliningrad exclave on the Baltic Sea. And, despite the COVID-19 pandemic, the Kremlin continues to organize snap exercises near NATO borders, alliance officials told The Daily Signal. 

Looking forward, most experts agree that Russia will continue looking for weak spots in NATO’s defenses, as well as for vulnerabilities in the alliance’s solidarity. 

Along that line of thinking, experts say it’s important for NATO to signal to Russia that the cancellation of Defender-Europe 20 is a one-off event, and that a broader retrenchment of U.S. forces, or a fracturing of the Western alliance, is not in the works.

“The larger issue that I foresee in the immediate term is to what degree Russia can exploit the current situation in the U.S. and Europe to undermine political cohesion through information war,” Gady said. “This worries me much more than a breakdown of conventional deterrence in Russia.”

Brave New World

So far, experts agree that NATO has sent the right message and Russia’s attempts to exploit the pandemic to its advantage, such as by sending medical supplies to Italy, have not splintered the alliance’s solidarity. 

In fact, some argue, one upside to the pandemic has been NATO’s ability to assist member countries hit hardest by the disease—such as Italy and Spain. 

At the end of March, for example, the U.S. Army announced that it was delivering supplies to Italy to help fight COVID-19. And other NATO forces have been continuously airlifting supplies where they’re needed.

“Russia might have counted on dividing NATO and playing on the expected lack of solidarity between the allies. Yet, it did not happen,” Terlikowski said. “As of now, allies have demonstrated that they do care about maintaining cohesion and solidarity, as they find NATO of utmost value for their security.”

Nevertheless, many experts warn that COVID-19 won’t leave the world a safer place in its wake. Consequently, they say, efforts to mitigate the pandemic must be done with an eye toward the eventual return to the so-called new normal of great power competition.

“Unfortunately, there is little likelihood that revisionist powers, like Russia or China, will drop their policy goals as an effect of the pandemic,” Terlikowski said. “In other words, the politico-military threats will not disappear with the pandemic, and in the post-COVID-19 world, the importance of deterring Russia in Europe will remain high for the U.S.”