President Trump hurts US globally, risks geopolitical recession, says Ian Bremmer

The U.S. very likely will lose its long-time role as the world's leader, with Donald Trump in the White House, warned top political scientist Ian Bremmer.

"A Trump presidency means the most significant hit to American power and leadership globally than any other event since the collapse of the Soviet Union," Bremmer, who is president of the Eurasia Group, said, adding that the billionaire's victory would see "the world heading into a profound (and longer term) geopolitical recession."

After 2008 financial crisis, the world had headed into a "geopolitical recession" defined by a growing vacuum of power in international politics amid waning influence from the G7 countries, he explained.

Ralph Freso | Getty Images

In a Eurasia post released on Thursday, Bremmer outlined three aspects of American leadership that would be affected by the election of the former reality TV star.

The first was the country's role as "world policeman."

Bremmer said that Trump will want to be "projecting strength around the world" and thus would likely expand U.S. military spending.

American objectives on terrorism, cybersecurity and non-proliferation of nuclear weapons would likely remain aligned with core American allies in Europe, Asia and the Middle East, he said. Bremmer expected Trump to work more closely with the Kremlin, however, while traditional alliances with Asian states and NATO partners would likely be challenged.

But "while a Trump administration is a challenge to global security issues, it doesn't suddenly upset the apple cart," he said.

Kliment: Can expect a warming of relations bewtween US & Russia
Kliment: Can expect a warming of relations bewtween US & Russia

The effectiveness of the U.S. as "trade architect" would be questioned, however, he said.

Trump's rhetoric has been anti-trade and protectionist in nature, with claims that American workers were suffering the effects of globalization.

"The Trans-Pacific Partnership (TPP) is a dead letter in this environment, as is the Transatlantic Trade and Investment Partnership (TTIP), [which is ] already on life support," Bremmer wrote.

He pointed out that China was prepared to finance alternatives to the U.S.-led trade architecture, which might see American allies edging away from the U.S. under a Trump administration.

President elect Trump vs presidential candidate Trump
President elect Trump vs presidential candidate Trump

Lastly, a Trump administration put America's role as a "values cheerleader" at risk, the high-profile commentator said.

Donald Trump, with his experience as businessman, would view international relations in a transactional manner, with "human rights and the like" taking a back seat," the political scientist warned.

"It's precisely the role of American values that most underpinned its strength as the world's superpower...That view has already eroded dramatically over the past decade...but President Trump intends to upend it," he said.

"America's footprint as the world's leader, and the role of Americanization in a globalized world, now pass the point of no return."

Follow CNBC International on Twitter and Facebook.