Few world leaders have so nakedly expressed the essence of the Westphalian state system, established by treaty in 1648, and under which every human being dwells today.

“As President of the United States,” Trump said, “I will always put America first, just like you, as the leaders of your countries, will always, and should always, put your countries first.” This is controversial? Every undergraduate learns this on the first day of International Relations. It is the first principle of the realpolitik practiced by Henry Kissinger, Winston Churchill and Otto von Bismarck.

Virtually every other American President has made the same point. President Barack Obama, expressing his conception of larger interests during his final speech before the United Nations in 2016, returned in the end to his own primary obligation – and that of his counterparts. “Sometimes I’m criticized in my own country for professing a belief in international norms and multilateral institutions. But I am convinced that in the long run, giving up some freedom of action – not giving up our ability to protect ourselves or pursue our core interests, but binding ourselves to international rules over the long term – enhances our security. And I think that’s not just true for us.”

Similarly, at the Rio Earth Summit in 1992, President George H.W. Bush – who didn’t even agree to show up until the last minute – declared, “I’m the President of the United States. I’m not the President of the world. And while I’m here, I’m going to do what best serves the interests of the American people.”

So what reason is there to believe that a couple of hundred sovereign nations pursuing their separate national interests will produce optimal outcomes for the whole of the human community? “The nation-state remains the best vehicle for elevating the human condition,” Trump declared to the UN. But he did not make a case for why that might be so. We live in a world whose crises interconnect us more than ever before. The runaway climate change that may have just produced three “thousand-year storms” in the space of three weeks. Genocide. Terror. Pandemic. The digital economy. An ever-increasing chasm of inequality, both within and among nations. An endless river of refugees generated by economic hopelessness – and global population totals that only go up. “Failed states” where national governments disintegrate and disappear. And most of all, succeeding generations not yet saved from the scourge of war.

All of these challenges are quintessentially transnational in nature. So, is it anyone’s job today – as primary responsibility, not just when it happens to coincide with a national interest – to discern and pursue the transnational interest, the common human interest, the global public good?

One answer, which could provide at least one small step for humanity tomorrow, is the proposal to establish a new international body called a United Nations Parliamentary Assembly. At the U.N., national “ambassadors” are currently appointed by executive branches of national governments. It is as if all 535 members of the United States Congress – House and Senate alike – were appointed by the governors of the 50 states. But on every lower level of governance – cities, states or provinces, and countries – we take for granted that the bedrock of democracy is some kind of legislature, whose individual members are selected by citizens at the ballot box. Why in the world can’t this exist on the global level as well?

A UNPA would seat individuals who had already been elected to national parliaments – the Japanese Diet and the U.S. Congress and the British House of Commons. It could be created by a simple vote of the U.N. General Assembly under Article 22 of the UN Charter. This would, for the first time in history, provide a direct voice on the global level not just for governments, but for people. Most importantly, its members would not answer to national governments, or articulate solely the interests of their national communities. They would be free to articulate the larger, collective interest of humankind – and to manifest not just the national patriotism of their voters, but a larger, planetary patriotism.

Some see the establishment of a UNPA as the first step on the road to democratizing our global institutions and representing our common humanity. One next step would be having UNPA members selected not from national parliaments, but elected directly by voters. Imagine going into the booth on Election Day in Chicago, for example, and casting your vote for candidates you believe will best represent your views in the Chicago City Council, the Illinois House and Senate, the U.S. House and Senate and the United Nations Parliamentary Assembly.

(I myself live in Washington, D.C., where voters are wholly disenfranchised on every level beyond the Council of the District of Columbia, but that’s another polemic for another time.)

Over time, the intangible authority that would emanate from resolutions passed by a UNPA – the international organization that would embody the collective views of all “citizens of the world” more than any other – would evolve into a more tangible authority. The U.N. General Assembly, the U.N. Security Council and national governments would find it increasingly difficult to take actions that directly contradicted opinions and debates and outcomes at the UNPA. Perhaps this new body might eventually provide the seeds for establishing what Alfred Tennyson envisioned in his poem “Locksley Hall” 180 years ago – a genuine Parliament of Humanity.

That kind of historical progression almost exactly mirrors what has already taken place in Europe. In 1952, as part of the nascent European Coal and Steel Community (ECSC), the contracting nations established a European Common Assembly (ECA). It was – just like a hypothetical future UNPA – made up of individuals who had already been elected to their national legislatures. At the outset, it too had a strictly advisory role. But today, the ECSC has become the European Union, and the ECA has evolved into the European Parliament, directly elected by European citizens, holding real power over many transnational matters, and the closest thing in the history of the world – so far – to a true supranational legislature.

The movement to establish a UNPA is rapidly gaining steam. Shortly before he died last year, former U.N. Secretary-General Boutros Boutros-Ghali said, “A Parliamentary Assembly at the U.N. has become an indispensable step to achieve democratic control of globalization.” The idea is pushed ardently in the United States today by Citizens for Global Solutions and the Democratic World Federalists, and internationally by the World Federalist Movement, the Young European Federalists and World Parliament Now. The Campaign for a U.N. Parliamentary Assembly based in Germany – focused exclusively on the UNPA objective – recently reported that more than 1,500 current and former members of national parliaments, from more than 150 countries, have now endorsed the proposal. (All these groups are collaborating on a “Global Week of Action for a World Parliament,” which begins Oct. 20) And the 2015 Commission on Global Security, Justice and Governance, co-chaired by former U.S. Secretary of State Madeleine Albright and former U.N. Under Secretary-General Ibrahim Gambari, not only advocated a U.N. parliamentary network, but called to bring it into being at a world summit on global governance during the U.N.’s 75th anniversary year in 2020 (where many other imaginative innovations in the structure of the U.N. system might be forged as well).

National leaders pursue the national interests of the national constituencies who elected them? Trump nailed it. No one can dispute it. But can we invent new structures of global governance that can give meaning to the 1955 Einstein-Russell Manifesto’s claim that its signatories spoke “not as members of this or that nation, continent, or creed, but as human beings, members of the species Man, whose continued existence is in doubt”?

Every American President, whether using the term or not, is going to put “America first.” But can we now begin to envision a future United Nations that puts humanity first?