Matt Bennett and Gabe Horwitz

Opinion contributors

Who lost Vietnam?

This question consumed American policymakers and scholars in the last quarter of the 20th century. Their focus was military: How could the mightiest fighting force in history lose to a third-rate army and some ill-trained guerilla fighters? But today, with Vietnam a friendly nation and a vibrant economy, the question is worth asking again. Because Vietnam is being lost anew, in both practical and metaphorical terms. We are, unthinkably, losing a different type of battle: President Trump is hollowing out our global economic power.

The measure of global strength in the last century — and in every century prior — was martial. Who had the greatest force of arms: the biggest arsenal, the best ships, tanks, and planes, and the best-trained and equipped troops? This, along with better strategic decision-making (DO NOT, for example, invade Russia during winter) would decide the global order.

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But today, the central importance of military strength is fading. Even the United States, the sole global hyperpower, has been unable to decisively defeat insurgencies in Iraq and Afghanistan. Our military alliances are fraying at the edges — Turkey is an ally only in the loosest sense — and we have no real military answers to threats like North Korea’s nuclear program or bad behavior like the Russian occupation of eastern Ukraine.

So the new locus of power in this century resides in treasuries, not arsenals. Nations rule the waves not through the might of their warships but by the profitability of their cargo ships. By this measure, the United States is a declining power. And Trump’s approach to the world, articulated in his new National Security Strategy (NSS), just hastens the fall.

The NSS, flawed on many levels, is egregiously off-base in the area of global economics. To begin with, Trump’s “America First” approach is isolationist and protectionist. It scoffs at his predecessors’ efforts at economic engagement. While paying lip service to free trade, the NSS promotes Trump’s promise to withdraw from the world and “build the wall,” both physically and metaphorically. He has taken the U.S. out of the 12-nation Trans-Pacific Partnership agreement and thereby handed control of commerce in the Pacific Rim — including trade with Vietnam — to China. China is already reaping the economic rewards. Trump has also alienated our most important trading partners in our own region, like Canada and Mexico. He has hollowed out the State Department and slashed foreign aid and investment.

And at home he is slamming shut the Golden Door with refugee and travel bans stacked against Muslims, egregious immigration crackdowns, and cuts to visa programs that help grow the economy. Now he has signed a tax law that will deliver precisely the wrong kind of sugar-high economic stimulus — tax cuts for the rich — and pile $1.5 trillion onto our already staggering national debt.

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The world has noticed America’s withdrawal from its leadership post, and China is already stepping in to fill the void. As part of its “One Belt, One Road” policy, China is spreading its influence to every corner of the globe, securing natural resources, opening new markets, and developing strategic alliances. China snapped up Greece’s main port at Piraeus to gain an economic and political foothold in the European Union — strapped for cash, Greece is in no position to argue with one of its biggest investors when it comes to regional political questions.

With hundreds of new infrastructure projects across Asia, Africa, Europe and even our own backyard of South America, China is creating new customers for its goods, new jobs for its people, and new leverage with its economic partners. China’s leader, Xi Jinping, has frequently been referred to as the world’s most powerful man and recently cast himself as the global defender of free trade, globalization, and liberal markets in his speech to the World Economic Forum in Davos. China’s ability to credibly claim the mantle of global economic leadership is a breathtaking, dangerous turnabout for the United States. This is how empires crumble.

It’s not too late to turn things around. If Trump stops destroying trade agreements, we could grow exports and influence. A reasonable approach to legal immigration would allow us to capitalize on our status as the leading intellectual powerhouse by recruiting and keeping the sharpest minds from around the world. Rather than splurging on huge and wasteful tax giveaways, we could invest in our workforce to help ensure that everyone, everywhere has the opportunity to earn a good life in this global and digital economy.

When we lost Vietnam the first time, the fear was of falling dominoes, handing the world to communism. This time, there are no precise pins in the map to chart our losses. But if we follow Trump’s “America First” economic agenda to its logical end, we will become “America Alone,” and China will replace us at the top of the global order.

Matt Bennet is a co-founder and senior vice president of the think tank Third Way. Gabe Horwitz is vice president for Economic Policy of Third Way. Follow them on Twitter: @ThirdWayMattB and @HorwitzGabe