BARCELONA (Thomson Reuters Foundation) - A global push to end poverty and hunger, and combat climate change by 2030 is at risk from American “militarism”, powerful business interests and the actions of President Donald Trump, said leading U.S. economist and U.N. special adviser Jeffrey Sachs.

The Columbia University professor said he was “not pessimistic” about the international agenda for sustainable development, adopted by the United Nations in 2015.

But he said harsh rhetoric raising the prospect of war with North Korea, and the domination of U.S. politics by billionaire businessmen may thwart progress toward the U.N. goals.

“More and more I see that while the kind of technical solutions I work on are very important ... the real obstacles that we are fighting every day are the political obstacles, the headwinds of powerful interests, bad ways of doing things,” he added.

In a live interview broadcast on Facebook, Sachs told the Thomson Reuters Foundation that Trump’s speech at the United Nations last week, in which he threatened to “totally destroy” North Korea, which is developing nuclear weapons, was “grossly dangerous and irresponsible”.

“We could actually avoid nuclear war - whether we will or not really is a guess,” he said, calling for diplomacy instead of the recent brinkmanship that shows “infantile misunderstanding of how dangerous this crisis is”.

Sachs, who has helped some 100 countries shape their policies, said he had expected to focus on international development issues “because the U.S. would more or less take care of itself” - but that no longer applies to his home nation.

“The horrible realization for me in the last 15 years ... is we’re not taking care of ourselves and more than that, we’re a danger to the world,” he said, whether it be through waging war in places like Iraq and Afghanistan, or failing to act on climate change.

Trump has said he plans to pull the United States out of the Paris climate agreement, adopted in 2015, arguing that cutting fossil fuel use would undermine the U.S. economy, cost jobs and weaken American national sovereignty.

CLIMATE COMPENSATION

Sachs said he thought there was still a “reasonable chance” the United States may stay in the Paris pact. Under its rules, Washington cannot completely withdraw until around the time of the next presidential election in 2020.

“The U.S. does stand alone right now - I don’t think other countries are going to fall into the trap of going anywhere close to Trump on this,” added the best-selling author.

There are no penalties for a country that wants to leave the accord or does not meet its voluntary commitments under the deal to keep global temperature rise “well below” 2 degrees Celsius.

But Sachs believes that in the same way tobacco firms were held liable for health damage from smoking, there will be a rise in class action lawsuits targeting major oil companies, such as Exxon Mobil Corp and Chevron Corp, seeking compensation for people suffering losses from extreme weather or rising seas that scientists link to climate-warming fossil fuels.

“We are going to sue you up and down the line when these horrible disasters occur, because you are responsible, because the damages have been foreseeable... and because you have been lobbying to forestall real action,” said Sachs.

The head of the U.N. Sustainable Development Solutions Network said he planned to launch a new political project on Oct. 9 that aims to set the United States on a path to achieve the global development goals, “honed to the U.S. context”.

He said he would seek support from both Democrat and Republican politicians for his “America’s Goals for 2030” initiative, adding that about two-thirds of U.S. citizens are in favor of a “progressive agenda”, including the provision of healthcare, clean water and unpolluted air.

“Americans like the idea of having clear goals, because we are going around in circles right now, and most Americans do not believe we are on a good track,” said Sachs. “I would say to all of you - get organized, from city government onward.”