Donald Trump may allow America’s last remaining nuclear arms control treaty with Russia to lapse. “If it expires, it expires,” he told The New York Times of the agreement, which runs out on 5 February.

If the New START agreement, signed in 2010, is not renewed or replaced, it would leave the “world’s two largest nuclear powers free to expand their arsenals without limit, for the first time in half a century”, said the paper.

What is it?

START (Strategic Arms Reduction Treaty) is a series of bilateral nuclear arms control treaties between the US and Russia, which began with START I in 1991. They aim to limit and reduce the number of nuclear weapons held by both countries.

The Week

Escape your echo chamber. Get the facts behind the news, plus analysis from multiple perspectives.

[

SUBSCRIBE & SAVE

](https://subscribe.theweek.com/servlet/OrdersGateway?cds_mag_code=TWE&cds_page_id=275740&cds_response_key=I4BRBKSW1&utm_medium=referral&utm_source=theweek.com&utm_campaign=wku-all-digital_referral-202401-sub-none-fbk24&utm_content=us-in-article)

Sign up for The Week's Free Newsletters

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

From our morning news briefing to a weekly Good News Newsletter, get the best of The Week delivered directly to your inbox.

Crucially, the New START agreement caps deployed strategic nuclear warheads at 1,550 each and delivery vehicles (such as missiles and bombers) at 700.

Will it be replaced?

Moscow and Washington are both “preoccupied by the war in Ukraine”, so they haven’t “held any talks on a successor treaty”, said Reuters, but there have been some informal statements from both sides.

In September, Vladimir Putin proposed that both parties should adhere to the START limits for a further 12 months. He has also argued that the nuclear stockpiles of Britain and France should be up for negotiation. Both countries have rejected that suggestion.

Trump hasn’t responded formally, but he told The New York Times that he would prefer a broader deal that could involve “a couple of other players,” without naming them.

A free daily email with the biggest news stories of the day – and the best features from TheWeek.com

Western experts are “divided” on Putin’s suggestion, said Reuters, because although it would “buy time to chart a way forward” and send a “political signal that both sides want to preserve a vestige of arms control”, it would allow Russia to keep developing weapons systems outside the scope of the treaty.

Then there is China. One US analyst argued that the US agreeing to Putin’s proposal would “send a message” to Beijing that Washington would not “build up its strategic nuclear forces in response to China’s fast-growing nuclear arsenal”.

Beijing has accelerated its nuclear programme and now has an estimated 600 warheads, but the Pentagon estimates it will have more than 1,000 by 2030.

Pavel Podvig, a senior researcher at the UN Institute for Disarmament Research, told Radio Free Europe/Radio Liberty that America may look to increase its stockpile in the face of this, which could lead to a “Cold War-like arms race”.

What does this mean for the world?

If New START simply expires, it would be the first time in around five decades that the world’s two largest nuclear powers would operate without any formal constraints on their arsenals. Between them, the two countries have about 87% of the world’s nuclear warheads.

But although the agreement saved superpowers “a bit of money” and provided a “forum that was useful for cooperation”, it didn’t “fundamentally change the probability of war”, Mark Bell, from the University of Minnesota, told New Scientist. It is the unthinkable results of nuclear conflict, rather than treaties, that prevent such wars, he said.

Putin has suggested that Moscow could voluntarily continue observing the limits if Washington did the same. The two countries could also share data about their deployed forces after the expiration.

As for Trump, he has previously said he would like to pursue “denuclearisation” with Russia and China to reduce the “tremendous amounts of money” each nation spends on nuclear weapons.