In the 2007 song “Planet Earth,” the recently departed Prince sings, “Fifty years from now, what will they say about us here? Did we take care of the water and the fragile atmosphere?”

What took place at the United Nations on Earth Day, when 175 nations signed onto the so-called Paris climate accord, might be seen as an important indication that the answer to Prince’s musical query would be, “Yes.”

Something so singularly significant – the nations committed to reducing greenhouse gas emissions that scientists agree are contributing to global warming and potentially disastrous planetary impacts – will demand a substantive conversation as well as decades of consistent commitment. It will not be easy.

But the effort, as made evident by this historic accord and recent polling, now clearly has the backing of governments and individuals across the globe.

In a Pew Research Center poll involving respondents in 40 countries and released in November, weeks before international diplomats gathered in Paris to hash out details of the just-signed agreement, 78 percent of people said they supported their country joining such an effort.

Two major outliers in the poll were, unsurprisingly, the world’s two largest greenhouse gas emitters. Respondents in China and the U.S., which respectively produce about 28 percent and 16 percent of global emissions, fell far behind others in their support, with only 18 percent the of Chinese and 45 percent of the Americans polled saying climate change is a very serious problem.

Although the European Union (10 percent of emissions), India and Brazil (6 percent), and Russia, Japan, and Canada (5, 3, and 2 percent, respectively) are also important players, China and the U.S. must lead or get out of the way, or the rest of the world could falter.

The poll also showed that the issue of climate change is fraught by partisanship in Australia, Canada, Germany, the United Kingdom and, to no one’s surprise, the U.S.

Enter the 2016 U.S. presidential race, in which the Democratic candidates, former Secretary of State Hillary Clinton and Sen. Bernie Sanders of Vermont, have made addressing global warming a key platform, while the two leading Republicans, well…not so much.

Donald Trump has called global warming a “hoax” and “conspiracy” despite 97 percent of climate scientists and many reputable national and international scientific bodies agreeing there is a major and developing problem with our environment being caused by humans.

The thing about conspiracy theorists is that many won’t listen to reason, as perhaps best articulated by the character Jerry (Mel Gibson) in the 1997 movie “Conspiracy Theory.” Jerry tells the character played by Julia Roberts, “A good conspiracy is unprovable. I mean, if you can prove it, it means they screwed up somewhere along the line.”

As for Sen. Ted Cruz of Texas, he has chosen to echo the glib perspective of former Vice President Dick Cheney, who once said he was sure the world experiences global warming, “or, as I prefer to call it, spring.” Cruz has said, “Climate change is not science, it’s a religion.” Some might find these statements humorous, but they’re inappropriate given the gravity of the issue.

Trump or Cruz becoming president in 2017 would surely mean a pull back in U.S. efforts to lead the charge to avoid what some have called a planetary catastrophe. Scientific climate research has prolifically documented that temperatures are increasingly higher than they’ve been in hundreds of thousands of years. In fact, last year was the warmest on record.

Temperature increases are melting polar ice caps and sea ice, resulting in rising sea levels, flooding of low-lying communities, the endangerment of critical animal and plant species, and population increases in disease-carrying insects like mosquitos. Concurrently, extreme weather events like heat waves, record droughts and concentrated clusters of intensified tornados are already being witnessed, and there’s more to come, all of which will negatively affect crop yields (think food security) and human life. These are the not-so-fun facts.

Environmental issues, specifically global warming, have not played a large role in the election campaigns so far. They should. What most of the world said on Earth Day is that addressing global warming is not only important but vital. The conversation deserves to be elevated in national dialogues and the U.S. election contests.

Meanwhile, we should celebrate the Paris accord, a prince of a deal for planet Earth.