One of the standard tropes of American politics is about global leadership. The automatic assumption on nearly all pressing issues is that we lead, and one of the charges typical of presidential campaigns is that the other candidate doesn’t, can’t or won’t lead. But now, on the most momentous concern of our time, a sizable number of the political class — including White House aspirants — are insisting we forego global leadership because the United States doesn’t matter to the fate of the issue.

That concern is climate change. The opportunity for leadership is tethered to a 20-year United Nations treaty process culminating in Paris in the next two weeks. And those saying it doesn’t matter are the big names in the Republican Party. Notably, this happened on different issues repeatedly in the past.

Recall, for example, the Paris Peace Conference and its Treaty of Versailles officially concluding the Great War (1914-1918). Among President Woodrow Wilson’s achievements as an emerging world leader was the creation of the League of Nations, a precursor to the United Nations. Republicans, in control of Congress, quashed American participation based on an isolationism that persisted for decades.

The isolationism wasn’t all selfish. Many Americans were rightly abhorred by the war, and war profiteers. But the absence of the United States from active involvement in burgeoning 1930s’ crises like the Italian invasion of Ethiopia, the Spanish Civil War, and the Japanese occupation of Manchuria all emboldened the rising fascist movement. The U.S. failed to lead until the Second World War came to our doorstep.

Perhaps it was America’s central military role in that war that led to a more inevitable, and natural, sense of leadership after the defeats of Germany and Japan. In the postwar period, the United States and its New Dealers created several global institutions — the United Nations, the World Bank, the International Monetary Fund — which themselves multiplied in the late 1940s and 1950s to include the World Health Organization, the Food and Agriculture Organization, and many others. (They also reconstructed Japan and Germany into democracies and economic powerhouses.) One can contest the effectiveness of the U.N., though on balance they stabilized the world economy and fostered prevention and aid.

This achievement of American leadership (including our funding of the U.N.) has been a target of derision and hindrance by the GOP’s right wing — which now dominates the party — from the 1940s. McCarthyism was the spear of the 1950s, when liberal internationalism still survived among Republicans, but conservatives always saw “world government” lurking in Turtle Bay and tried to subvert it at every turn, and this persisted right through the George W. Bush presidency.
Now we come to another crossroad where U.S. leadership will be decisive.

The 21st Conference of Parties (COP21) is gathering in Paris to reach a final agreement to reduce, voluntarily, carbon emissions. It may be the last, best hope to stave off catastrophic climate change. Because pledges of carbon reductions are made by each country, and the pledges will be self-enforced, the COP21 agreement is a fragile instrument.

As a result, leadership from the world’s advanced industrial countries–those will the largest carbon footprints — is indispensable.

If the United States does not move assertively to meet its own target reductions (25-28 percent below 2005 levels by 2025), help develop renewable technologies, and aid poorer countries to meet their pledges, the entire accord could unravel. Leadership in this case also means pressuring China, Russia, and India — all reluctant players — into compliance, and making that a bilateral priority.

President Obama and the Democratic Party generally have a mixed record on global warming, but it’s improved of late and Obama seems poised to lead, as do any of his possible Democratic successors.

The Republicans, however, are again acting as spoilers. Some among the presidential field have switched from outright denial of the science of climate change to the attitude that it doesn’t matter if the United States plays any role. It’s an odd piece of logic from a group that typically howls about the need for stronger U.S. leadership on virtually all other issues. And the climate-change deniers are still at it, too.

Note that it’s more than rhetoric: Republicans are actively subverting Obama’s leadership. As reported in Politico, “The GOP strategy … includes sowing doubts about Obama’s climate policies at home and abroad, trying to block key environmental regulations in Congress, and challenging the legitimacy of the president’s attempts to craft a global agreement.” This includes telling other governments that the U.S. is an unreliable partner on this issue.

They are making good on their threats. Congress voted earlier this month to block the Clean Power Plan, Obama’s sensible scheme to clean up power plant pollution in particular. The GOP leadership on the Hill threaten to block any aid to poorer countries to reduce carbon emissions (a key part of COP21), and are continuing their assault on the Environmental Protection Agency.

It is an embarrassing spectacle, unique among world powers. But the embarrassment is trivial. The United States, until recently the world’s biggest polluter, is now second to China but still accounts for one-fifth of the world’s carbon emissions. The sheer scale of our carbon footprint argues for a leadership role, but it is also the unique quality of U.S. standing in the world — our economic, technical and normative power — which is equally if not more important to a successful outcome at Paris and beyond.

Anti-Obama hysteria and the relentless anti-science bias of the Republican Party account for these reckless actions on Capitol Hill. Fortunately, virtually every player at the Paris conference fully understands the grotesque extremism gripping the GOP. It is literally the only major political party in any country that believes climate science is a hoax and that nothing should be done to curb carbon emissions.

Still, more than ever, the stakes involved in U.S. leadership are the highest conceivable. Let’s watch to see who steps up to the challenge.

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