From the “culture wars,” to “battleground states,” to “social justice warriors,” military metaphors have become a ubiquitous feature of the current political landscape. I have previously condemned this trend as melodramatic and insincere, but as a student of American national security issues and an advocate for multi-partisan civil dialogues, I see no greater threat to the security and well-being of Americans than the hyper-polarization of our society.

Lincoln’s warning that “A house divided against itself cannot stand” rings as true today as at any point in our history. Our division at home is more serious than any threat emanating from abroad because it poses a triad of dangers to the United States—hyper-polarization fuels violence across the Union, acts as a “threat multiplier” that makes other threats worse, and will erode the sources of American strength for generations to come.

After the Jan. 6 insurrection at the United States Capitol, it is now undeniable that the deep animosity that some Americans hold toward fellow citizens can claim innocent lives. After media coverage seared images of violent mobs ransacking the Capitol into the American psyche, this clear and present danger cannot be overlooked. Only a few weeks before the chaos in Washington, a conspiracy theory-inspired bombing in Nashville might have been a mass casualty were it not for the quick response of courageous police officers. Since 2016, hate crimes have spiked from about 6,000 to well over 7,000 each year. A recently released unclassified summary of a federal intelligence assessment concluded that racially-motivated domestic extremists are “most likely to conduct mass-casualty attacks against civilians” and “government personnel and facilities.” While hate crimes do not include crimes that target individuals based on political belief, the rise of identity politics that pits certain identity groupings against others has led a small but significant number of Americans to resort to violence.

Beyond the immediate threat, our polarization makes every single other security issue worse by frustrating our ability to agree on and implement solutions. The Homefront mobilization effort to win WWII would likely have had a different outcome if a large share of Americans believed that the war was a waste of time. After WWII, Republicans and Democrats agreed across multiple administrations that the Soviet Union was a threat to American national security. Without this domestic cohesion, it would have been far more difficult to maintain the levels of peacetime military preparedness in order to deter Soviet aggression.

On top of the obstacles to formulating a grand strategy, polarization complicates responses to seemingly mundane problems. For example, during the recent winter storm in Texas, widespread power outages sparked partisan bickering over whether advocates of the “Green New Deal” were to blame. Instead of politicians mobilizing the government to deliver basic supplies and services to affected populations, a round of salvoes in the culture war took time and attention away from the disaster response.

Our divisions are also a critical vulnerability that malign actors can exploit. I am hardly the first to acknowledge that Russia did not invent the societal fissures that it skillfully and insidiously targeted during the 2016 election. In a matter of years, QAnon went from a fringe conspiracy group to a movement with congressional endorsements. Social media companies have gradually pushed back against foreign disinformation campaigns, but adversaries continue to adapt. In one instance, a Russian disinformation outlet called NewsFront used “mirror sites”—other domain names that replicate NewsFront’s content—thereby circumventing the bans placed on it by most social media platforms. The problem is not about supply but rather demand—the weaponization of our internal divisions cannot be filtered out by Big Tech. Rather, it must be rejected by the consumers of digital media.

Hyper-polarization is a crisis that no act of Congress or executive order can fix. It will be an intergenerational struggle to heal the wounds of decades of growing partisanship and political dysfunction. However, the long-term costs are too great to give in to defeatism. These costs are explored in one of the best recent books on the polarization crisis, David French’s “Divided We Fall.”

French’s recent experiences in many ways epitomize the recent American experience. He served in Iraq as an Army Judge Advocate-General, a military lawyer that represents soldiers in court-martials and advises officers on legal matters in the conduct of war, and returned to the U.S. to become a First Amendment litigator and conservative columnist. French grew estranged from the Republican Party as it became more radical, and he decisively broke from the party shortly after the nomination of Donald Trump.

The subtitle of French’s book, “America’s Secession Threat and How to Restore Our Nation” might strike some as sensationalist, as it did for me when I first read the front cover. Yet, French’s scenarios for how the United States might break apart are eerily plausible. According to French, the geographic sorting of subcultures and the fear that opposing groups have malign intentions combine to propagate the idea that liberal America and conservative America cannot coexist under one federal government. An entire chapter is dedicated to how the potential fracturing of the United States would undercut its leadership position and create global instability. A “Disunited States” would be unable to deter Russian incursions into Eastern Europe or guarantee security to our Japanese, Taiwanese, and South Korean partners.

A polarized America is dangerous to Americans and dangerous to the world. However, no number of aircraft carriers, tanks, and bombers can deter this threat. To indulge in a military metaphor, what is needed is a counter-insurgency at home—a battle for the hearts and minds of Americans to prove that we are better off together than we are apart.

The American college campus is often identified as the epicenter of this crisis. However, my experience as a discussion organizer and moderator for the Texas Political Union and BridgeTexas through my four years of college is that young people are uniquely suited to overcoming this challenge. Success in these efforts is not about achieving consensus or winning the debate. Rather, can we encourage courageous displays of vulnerability from the left and the right and seek a better understanding of what divides and unites us? One Texas Political Union event held after the raucous demonstrations during the nomination of Supreme Court Justice Brett Kavanaugh demonstrated to me that students are able to have hard conversations without losing sight of the other side’s humanity. Yet despite these successes, I still worry about whether political divisions on campus are getting better or getting worse.

There is more work to be done. I am grateful that platforms like The Texas Orator and organizations like BridgeTexas exist to foster the free exchange of ideas. There is nothing wrong with finding like-minded friends, but I have experienced the most personal growth from discussions with differently-minded people who I am lucky to share friendships with.

I hope future classes of college students will take up this quest for common ground. Large universities like The University of Texas at Austin become home for students across the state, across the country, and across the world. There is no better place to start the long journey to overcoming our partisan divisions and ensure that Lincoln’s “braver angels” shall prevail.