As the United Nations this week warned the world's ocean are "under threat as never before" from global warming and other human activity, Bolivian President Evo Morales took direct aim at President Donald Trump by saying his decision to withdraw from Paris climate agreement proves the United States is now the "main threat to mother Earth and life itself."

Addressing the first international Oceans Conference at the UN headquarters in New York City on Monday, Morales charged that by rejecting the scientific consensus and ditching the landmark agreement, the U.S.—the world's largest driver of greenhouse gas emissions and its "main polluter"—was "denying science, turning [its] backs on multilateralism and attempting to deny a future to upcoming generations."

"The history of the United States is the exploitation of peoples and natural resources of the [Global] South. Its current wager: to destroy Mother Earth." —Bolivian President Evo MoralesAt the conference, Deputy Secretary-General Amina J. Mohammed drew on on scientific findings and reporting from around the world to paint a troubling picture of the peril now facing the world's ocean.

"Globally, the sea level has risen by 20 centimetres since the start of the 20th century," Mohammed stated, "due mostly to thermal expansion of the oceans and melting of glaciers and ice caps. Some regions are experiencing even greater sea level rise." Overall warming trends, acidification, coral bleaching, and sea leve rise, she continued "are affecting eco­systems in all regions, threatening fisheries, food chains and the oceans' ability to act as efficient carbon sinks."

In his opening remarks to the event, Secretary-General Antonio Guterres said the oceans—which he called "the lifeblood of our planet"—harmed by warming, pollution, and exploitation by industry are currently "under threat as never before."

According to Guterres, "Improving the health of our oceans is a test for multilateralism, and we cannot afford to fail." He called on the world leaders gathered in New York to set "aside short-term national gain to prevent long-term global catastrophe. Conserving our oceans and using them sustainably is preserving life itself."

If not addressed with urgency, Mohammed warned, the results this century will be "catastrophic for coastal habitats and economies" and "hundreds of millions of people" are now at risk.

It was for these reasons and others that many have come to share Morales' dim view of U.S. leadership under Trump and the Republican Party.

Last week, in the immediate wake of Trump's announcement about Paris, Morales decried the decision while putting it in historical context. "The history of the United States," he said, "is the exploitation of peoples and natural resources of the [Global] South. Its current wager: to destroy Mother Earth."