In 2015 and 2016, Donald Trump ran a campaign that exploited the ignorance of many voters on the benefits of free trade to gain popularity in certain uneducated sects of the American populace. In his ignorant tirades against conventional trade wisdom, he particularly demonized the North American Free Trade Agreement of the Bill Clinton administration, and the proposed Trans-Pacific Partnership of Obama’s administration.

Some Democrats have unfortunately bought into Trump’s foolish premises on free trade, most notably Bernie Sanders. Bernie is shockingly proud of his record opposing liberal trade policies, even tweeting a list chronicling his own isolationist voting record on the issue.

Liberals should stand in opposition to the populist tides of a domestic polity increasingly hostile to a more cosmopolitan and globalized world, and instead champion liberal, internationalist trade policies.

The benefits of free trade are plain to anyone who understands basic economic theory, and it is a rare point of consensus between right and left-leaning economists, from Milton Friedman all the way over to Paul Krugman. Globalization is the natural consequence of free trade among countries and is by all reasonable estimations, the exchange of culture as well as goods between countries has been an unmitigated cultural and economic boon.

But liberals should not restrict themselves to the advocacy of free trade pacts like NAFTA or the TPP, though both are esteemed measures worth implementation. Policies of free trade should instead be seen as good first steps toward more globalized governance.

Proponents of Brexit in England can bluster to their heart’s content about the supposed benefits of sovereignty at the cost of mutual cooperation, but what their jingoistic tirades always fail to attack is the roaring economic success the European Union has seen since the implementation of the Schengen Agreement in 1995. Schengen effectively rendered the interior of the European Union borderless which, according to one 2014 study, resulted in a “boost in immigration results in hundreds of millions of dollars of increased trade every year.”

American liberals should too aim for a North American Union with a similar arrangement of a free flow of goods, labor and services between the USA, Mexico and Canada, with the end goal of, in the reported words of Hillary Clinton in 2016, “a hemispheric common market, with open trade and open borders, some time in the future with energy that is as green and sustainable as we can get it, powering growth and opportunity for every person in the hemisphere.”

This plan would of course have naysayers, as even the best of ideas do. From the political right, many of the same tired tropes will be re-used from the Brexit campaign – namely concern-trolling sovereignty, along with conspiratorial fear-mongering about immigrants taking jobs and whatnot. The far-left will probably object for similar reasons, citing an unfounded need for economic protectionism to shield the working class.

American trade protectionism is a bad policy in any form, whether the intentions are well meaning or not. Not only does it forgo the massive potential benefits of free trade for developed countries, but it prevents less-developed countries from participating in the mutually beneficial practice of trade.

The European Union example is apt to prove this point as well – in the years following Poland’s membership in the union, “the export of goods from Poland grew by 31% and 19.6% to € 55.1 billion in 2005, to € 67.6 billion in 2006, to € 80.3 billion in 2007, to € 90.4 billion in 2008,” according to one study. That trade was accompanied by an unprecedented level of growth in Polish history, including an expansion of GDP from $255.28 billion in 2004 to $533.8 billion in 2008.

The question that should be asked of opponents of globalization shouldn’t just be restricted to probing those with anti-immigrant views. They should also be asked why they oppose policies that will help the global poor, as policies of open trade and borders demonstrably do.

Dylan Meisner is a sophomore studying political science and international security and conflict resolutions. Follow him on Twitter @DylMeisner.