America entered the Great War a hundred years ago this month. This is the second installment of our brief discussion about some of the lessons of the war. In the first, we talked about the limitations of treaties and the importance of deterrent military strength. Today, we look at three more lessons from the Great War that can be applied today.

Lesson Number Three: Democracy may be easy to plant, but it takes time, effort and (usually) outside assistance to grow. President Woodrow Wilson envisioned a world “made safe for democracy.” Yet as historians Felix Gilbert and David Large note in their history of modern Europe, “After 15 years, with the exception of Czechoslovakia, not one of the states created or reorganized at the Paris Peace Conference remained a democracy.” In fact, some pieces of postwar Europe—Soviet Russia, Nazi Germany, Fascist Italy—became virulently anti-democratic.

As for Czechoslovakia, its sovereignty and democracy were sacrificed for the false promise of “peace in our time.” Though un-invited to Munich, Czechoslovakia was not silent. Indeed, it was Czech Foreign Minister Kamil Krofta who brought the betrayal at Munich into focus. “Today it is our turn,” he concluded. “Tomorrow it will be the turn of others.” He was correct. Within a year, Hitler invaded Poland, Stalin gobbled up the Baltics and World War II was underway.

Recent polls reveal that just 22 percent of Americans say the U.S. should “promote democracy and freedom in other countries”—down from 70 percent in 2005. Reflecting the national mood, President Barack Obama scaled back democracy-promotion initiatives; focused on “nation-building at home”; mustered muted reactions when Iran’s democracy movement came under assault; left proto-democracies in Iraq, Libya and Ukraine to fend for themselves; and, with the help of the bipartisan gamble known as sequestration, shrank the reach, role and resources of democracy’s greatest defender—America’s military.

President Donald Trump promises more of the same, albeit in a roundabout way. In a surprising echo of Obama, Trump argues “We have to build our own nation.” He embraces an “America First” foreign policy and says his threshold for military intervention is “a direct threat to our interest.”  He even describes “trying to topple various people”—we can infer he was talking about Saddam Hussein and Muammar Kaddafi—as “a tremendous disservice…to humanity.” In short, there’s no hint in Trump’s don’t-tread-on-me nationalism of Wilson’s determination to “fight for the things which we have always carried nearest our hearts—for democracy,” for “the rights and liberties of small nations,” for “political liberty.”

Given the words and actions of Obama and Trump, it’s no surprise that democracy is in retreat around the world. As Freedom House details in its latest survey, “A total of 67 countries suffered net declines in political rights and civil liberties in 2016, compared with 36 that registered gains…the 11th consecutive year in which declines outnumbered improvements.”

If America no longer has the will to promote democracy, we must at least protect democracy by returning to what President Franklin Roosevelt called “armed defense of democratic existence.” Today, that means maintaining the strength to deter rising autocracies (China), revisionist governments (Russia) and rogue regimes (Iran and North Korea). In addition, in FDR’s words, “Let us say to the democracies: ‘We Americans are vitally concerned in your defense of freedom. We are putting forth our energies, our resources and our organizing powers to give you the strength to regain and maintain a free world.” Today, that means vocal and muscular support for treaty allies in Asia and Europe. It means arms for Ukraine rather than MREs. It means direct military aid for the Kurdish Regional Government. It means Taiwan deserves the defensive weapons it has been promised. Without this support, the roster of democracies will continue to shrink, this ugly age of strongmen will continue to cast its dark shadow, and America will grow less secure. Wilson understood that a world divided between dictatorships and democracies was inherently dangerous for America. Thus, when he talked about making the world “safe for democracy,” he was talking about building a safer world for the United States.

Lesson Number Four: Trade isn’t a failsafe inoculation against war. German iron-ore imports from France grew 60-fold in the 13 years before the Great War. In 1914, Britain accounted for more than 14 percent of Germany’s exports. These trade links did nothing to address other factors: Germany’s desire for a slice of Europe’s colonial pie, distrust among European powers, territorial disputes, secret security guarantees, the disconnect between democratic and authoritarian states.

As before the Great War in Europe, trade is booming in Asia: Japan-China trade is $303 billion annually; U.S.-China trade is $579 billion annually. And as before, there is a rising authoritarian power that feels hemmed in and entitled (see China); strategic uncertainties abound (consider the question marks created by Trump’s America First doctrine, which follows Obama’s stand-off foreign policy); territorial claims remain unsettled (see the South China Sea); and the scope of treaty commitments is uncertain (note the anxiousness of allies in the Pacific and Eastern Europe). In fact, Japanese Prime Minister Shinzo Abe sees his nation and China in a “similar situation” to Britain and Germany on the eve of World War I. Likewise, Kevin Rudd, former prime minister of Australia, sees parallels to prewar Europe in today’s Asia-Pacific—a region “riven by overlapping alliances, loyalties and hatreds,” and simmering with a mix of “primitive…nationalisms” and “great-power politics.”

We can hope that America has enough residual muscle to maintain the balance, that Washington begins to speak with sufficient clarity to prevent miscalculation, that trade ties prevent a great war in the Pacific. But as historian Robert Kagan ominously warns, “The United States and China are no more dependent on each other’s economies today than were Great Britain and Germany before World War I.”

Finally, when applying lessons from the Great War, we should take care to draw the right lessons. A common refrain is that Europe’s arms race triggered World War I. If this were true, then a) there shouldn’t have been a World War II, since the Allies allowed their arsenals to atrophy after World War I, and b) there should have been a World War III, since Washington and Moscow engaged in an unprecedented arms race after World War II.

The reality is that miscalculation lit the fuse of World War I. The antidote, as we have learned in the intervening century, is clarity plus strength. Arms alone aren’t enough to deter war. The great powers were indeed armed to the teeth in 1914. But since they weren’t clear about their treaty commitments, a small crisis on the fringes of Europe mushroomed into a global war. Nor is clarity alone enough to deter war. Wilson’s words and warnings to the Kaiser were clear, but America lacked deterrent military strength to back up those words.

The men who crafted the West’s post-World War II blueprint applied the clarity-plus-strength model to prevent the Cold War from boiling over. But with America’s words doing more to worry allies than reassure them—and America’s deterrent strength being whittled away—it seems Washington has abandoned that blueprint. If so, we have much to worry about. “The United States never learns by experience but only by disaster,” President Theodore Roosevelt observed. “Such method of education may at times prove costly.”