U.S. President Donald Trump (R), French President Emmanuel Macron (L) and German Chancellor Angela Merkel (C) at the start of the first working session of the G-20 meeting in Hamburg, Germany, on July 7, 2017.

While listening to President Trump announce the European travel ban in his Oval Office address, my mind wandered back in time to the early G20 meetings of finance ministers and heads of government in 2009 when the United States and its European partners worked together to head off a global financial meltdown.

I then traveled back a little further in time to the terrorist attacks of 9/11, a day on which I found myself traveling on the Eurostar between London and Brussels, my two homes at the time. For the first time in NATO's history, our European and Canadian allies triggered the alliance's Article 5 commitment to common defense.

Going back to read the language of this provision, written in 1949 to deter Soviet aggression, it struck me that Trump could have produced a far more presidential moment this week if he had done what the Europeans did for the United States back then. He should offer the transatlantic community an Article 5 declaration of war against this deadly pathogen.

If NATO could bend Article 5 to combat a non-state terrorist actor striking the United States, why not also to combat the Chinese-originated COVID-19, which by Friday had infected more than 28,000 individuals and killed more than 1,200 among NATO allies. Given current transatlantic divisions, there is far greater need now than after 9/11 for a symbolic gesture of unity.

President Trump could have confounded his critics, calmed markets and perhaps even outlined common cause efforts – including travel limitations – that he and his administration had agreed to during consultations with our NATO partners and the European Union. "Article 5 provides that an attack on one of us is an attack on all," he could have said, Three Muskateer-like. "It's all for one, and one for all!"

There's also a strong America First reason why President Trump should have leaned more in that direction. He's going to need Europe, just as the United States did in 2009, as this health crisis is quickly becoming a markets and financial crisis that could be addressed far more effectively through coordinated public health and fiscal stimulus measures.

Though no one wishes the world a financial crisis of the 2008 and 2009 dimensions, it would be irresponsible not to begin talks among the world's major economies and democracies about what strains they see in the system and what contingency planning they should be undertaking should the coronavirus economic slowdown continue. Compared to 2009, the world's record debt levels and its low to negative interest rates provide far less capability and then demand even more common cause.

Instead, what unfolded on 3/11/2020 in Europe and the United States were events that further underscored how divided the United States and its European partners are when they should be most united. Without consulting our allies at all, he implemented the ban – which took effect at midnight Friday in an Oval Office address on all American television networks that left his own national security team scratching their heads, correcting mistakes (cargo wouldn't be banned, as the President initially said), and filling in critical omissions (Americans could still travel home from Europe).

The result was one of the harshest responses ever recorded from EU leaders to an American President. A joint statement by President of the European Commission, Ursula von der Leyen, and President of the European Council, Charles Michel, read: "The Coronavirus is a global crisis, not limited to any continent and it requires cooperation rather than unilateral action. The European Union disapproves of the fact that the U.S. decision to impose a travel ban was taken unilaterally and without consultation. The European Union is taking strong action to limit the spread of the virus."

"When it comes to solidarity and unity, the United States is failing the coronavirus test," Benjamin Haddad, the director of the Atlantic Council's Future Europe Initiative, wrote in the Washington Post. "President Trump's speech Wednesday on the response to COVID-19 marked one of the most consequential foreign policy turning points of his presidency. This moment represents the lowest point in transatlantic relations in recent memory."

Sadly, the recent days have also shown how divided Europeans are among themselves, with Italians that there call for help has brought insufficient assistance to the country so far hardest hit in Europe by the virus. At previous such times of European uncertainty, the United States could provide necessary glue to keep everyone together.

"….it's time now for the EU to go beyond engagement and consultations," Maurizio Massari, the Italian permanent representative to the European Union, wrote in Politico, "with emergency actions that are quick, concrete and effective."

He complained that "not a single EU country" had responded to Italy's call to active the European Union Mechanism of Civil Protection for the supply of medical equipment for individual protection. "Only China responded bilaterally. Certainly, this is not a good sign of European solidarity."

Unimaginably, Italian newspapers were full of Beijing's outreach to help on the very same day that President Trump declared his European travel ban.

A plane carrying a team of specialist doctors with battleground experience fighting the virus left China on Wednesday for Italy, the European epicenter of the pandemic, with urgently needed medical equipment. That includes 2 million facemasks, 20,0000 protective suits and 10,000 ventilators.

The gesture was widely publicized in China and Italy. A report in China Daily said that thanks to donations from people living in the East China Zhejian province, some 4,556 boxes of disaster-relief materials were on their way to Italy. More than 300,000 people from the province live and work in Italy.

Crises either make institutions and relationships stronger or weaker, but they don't leave them unchanged. A pandemic's political danger is that countries – just like some individuals – feel that it's everyone for themselves.

Yet after an unforgivable initial delay, Europeans are beginning to show more solidarity among themselves. EU leaders have committed 25 billion euros to respond to the economic fallout, of which $7.5 billion euros should be available quickly to provide emergency necessities.

Now it's the United States' turn to mend the message of this week. As fanciful as this idea might sound, it's time to invoke NATO's Article 5 to tackle the virus. It may take that dramatic of a symbolic action to repair the transatlantic damage that has been done.

Frederick Kempe is a best-selling author, prize-winning journalist and president & CEO of the Atlantic Council, one of the United States' most influential think tanks on global affairs. He worked at The Wall Street Journal for more than 25 years as a foreign correspondent, assistant managing editor and as the longest-serving editor of the paper's European edition. His latest book – "Berlin 1961: Kennedy, Khrushchev, and the Most Dangerous Place on Earth" – was a New York Times best-seller and has been published in more than a dozen languages. Follow him on Twitter @FredKempe and subscribe here to Inflection Points, his look each Saturday at the past week's top stories and trends.

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