During arguments before the U.S. Supreme Court recently on whether to require the EPA to regulate greenhouse-gas emissions, Justice Antonin Scalia stated, “You have to show that harm is imminent.”

Well, perhaps an ancient ice shelf the size of 11,000 football fields breaking off Ellesmere Island might be an indicator. The collapse of the ice island's northern coast in the Canadian Arctic was at a speed and size that startled scientists.

Or the fact that this year was the third-warmest in record-keeping history.

Or maybe the mounting pile of scientific evidence that the warming of the earth’s temperature is going to cause monumental problems, from a melting Antarctic to devastation from rising sea levels, would be enough to answer Scalia’s questions.

Of course the pseudo-science suggesting things are just fine continues to give ammunition to those who do not want any government action to begin limiting the burning of fossil fuels that speed global warming.

Many of those studies have been funded by — here’s a surprise — ExxonMobil.

Sens. Jay Rockefeller and Olympia Snow recently called on the oil giant to stop funding studies aimed at confusing the body of scientific evidence that indicates global warming is a real and imminent danger.

Those who don’t want the Supreme Court to rule that the EPA has some obligation to limit gas emissions note that other countries would continue to burn fossil fuels unabated.

But more Americans and policy makers understand that abatement of greenhouse gas emissions needs to start somewhere, and starting with the world’s superpower is not only reasonable but morally supported.

If the high court, as seems probable, provides a 5-4 vote against listing emissions as a regulatory obligation, then Congress should provide guidance for the country’s environmental agency.

If the United States won’t lead the way, who will?