Trump likes to threaten withdrawing the US from NATO. But can he really do it?

Donald Trump says he is not afraid to pull out of the North Atlantic Treaty Organisation (NATO), but can the US really withdraw from the agreement?

The US President has repeatedly threatened to pull out of the 77-year security alliance with Canada, the UK, France and 28 other European countries as early as his first term.

Most recently, he has criticised NATO for its failure to help US military objectives in Iran.

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But Trump's latest remarks have people worried.

When asked if he would reconsider US membership in NATO, Trump told the Telegraph that it is "beyond reconsideration".

"I was never swayed by NATO. I always knew they were a paper tiger, and Putin knows that too, by the way," he said.

What is NATO?

NATO, formally known as the North Atlantic Treaty Organisation, was established in 1949 with 12 core member countries, including the US, Canada, the UK, France and Denmark, and has since expanded to 32 members.

The treaty was initially created as a form of collective security against the spread of the Soviet Union and communism in Europe following World War II.

The heart of the treaty is article 5 in the charter, which states that an armed attack against one or more member countries will be considered an attack against them all.

They all agree to help the countries being attacked, including through armed force.

The only time this measure was ever invoked was after the 9/11 attacks in New York when NATO members sent troops to support US military efforts in Afghanisation.

Trump has been critical over NATO members for failing to help the US military in Iran, however the US was not under attack when it launched a joint war against Iran and NATO members are under no obligation to .

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Why does Donald Trump seem aggrieved with NATO?

Trump has repeatedly raised concerns with NATO since his first term as president.

His source of pain seems to be the belief that the US does more for the treaty than its European members, telling Reuters on Wednesday that NATO is a "one-way street".

All NATO members contribute to a shared defence budget to maintain the treaty and defence operations.

The US accounts for roughly two-thirds of the treaty's total defence spend.

This is, however, because the US has an estimated higher GDP than all the 31 other NATO countries combined.

Trump has also been critical of treaty members' defence spending, which used to be a target of two per cent of their individual GDP.

NATO members seem to be trying to keep the peace and in June agreed to raise their defence spending target to five per cent of their GDP by 2035.

The US spends about 3.4 per cent of its own GDP on defence but, because of its higher GDP, that figure equates to almost $1 trillion.

Tensions have also arisen from Trump's repeated threats to take control of Greenland, which is a territory of Denmark (a treaty member).

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Can the US actually withdraw from NATO?

Yes, but it won't be easy.

First, Trump will need to convince the Senate or Congress to support his decision to do so.

A law passed in 2023 makes it illegal for a president to "suspend, terminate, denounce, or withdraw the United States from the North Atlantic Treaty" without the advice and consent of the Senate or an act of Congress.

This was introduced after Trump's repeated threats to leave NATO raised concern about whether he actually had the power to withdraw without approval.

While Democrats largely support the treaty, there is mixed support from Republicans.

Then, Trump will have to provide all the NATO countries a formal, written notice of his withdrawal a year before it can take effect.

Article 13 of the NATO charter states that "any Party may cease to be a Party one year after its notice of denunciation has been given to the Government of the United States of America, which will inform the Governments of the other Parties of the deposit of each notice of denunciation".

In saying that, Trump has bypassed rules and laws before. The most recent example being when he failed to seek approval from Congress before attacking Iran on February 28.

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