J EREMY CORBYN has the most radical views on national security of any leader in the Labour Party’s history. He is a long-standing opponent of both NATO and nuclear weapons. He has called Hamas and Hezbollah “friends”. Faced with overwhelming evidence of Russian state involvement in the poisoning of two people in Salisbury, he first obfuscated and then demanded that Russia should be involved in the investigation.

And yet the public has remained surprisingly indifferent to these brutal facts. In the election of 2017, the right-leaning press launched a fierce attack on Mr Corbyn’s foreign-policy views. Readers yawned. This time the bombardment has started again, but to no obvious effect. The only national-security question that has caught fire is the government’s refusal to publish a parliamentary report on alleged Russian meddling in British politics.

Mr Corbyn has been protected from proper scrutiny by three convenient assumptions: that his heart is in the right place; that he will drop his “ban the bomb” idealism when confronted with reality; and, third, that Labour moderates will be able to control him. Let’s examine each of these in turn.

Mr Corbyn is, in fact, very far from the cuddly pacifist of Glastonbury lore. The core of his beliefs is not opposition to war but opposition to “Western imperialism”. His hostility to “imperial powers” (most notably America and Israel) is so fierce that he is willing to make excuses for “anti-imperial powers” such as Russia and Syria, as well as terrorist organisations like Hezbollah and Hamas. His support for national liberation movements stops short of support for the people of Crimea, Georgia or Ukraine. His sympathy for victims of oppression turns cold when the countries doing the oppressing are Vladimir Putin’s Russia, Nicolás Maduro’s Venezuela or, in the 1990s, Slobodan Milosevic’s Serbia. In a speech in 2014 celebrating the 35th anniversary of the Iranian revolution, he praised the regime’s “tolerance and acceptance of other faiths, traditions and ethnic groupings”.

Mr Corbyn is no more likely to drop these views than he is to join the SAS . A geopolitics obsessive, he has been banging the same drums since the late 1970s, if not before (his parents were subscribers to the propaganda sheet, Soviet News). If anything, his views have hardened. In 1999 and 2000 he signed a number of parliamentary motions criticising Russia’s invasion of Chechnya. More recently he has bent over backwards to excuse Mr Putin’s adventures in his near abroad (and indeed in Salisbury). Since taking over as Labour leader in 2015 he has surrounded himself with advisers, such as Seumas Milne and Andrew Murray, who have spent their lives on the farthest fringes of the far left.

What about the idea that all this is hot air? Labour moderates (who constitute the vast majority of the party’s MP s) will step in to prevent Mr Corbyn from wreaking havoc, the argument goes. And besides, he will probably be able to form a government only in alliance with other parties, most prominently the Scottish National Party ( SNP ). Mr Corbyn has abandoned his opposition to Britain’s trident missile system under pressure both from his MP s and from Len McCluskey, the head of the Unite trade union, who thinks that jobs trump geopolitics. And most of the day-to-day work of defence and security is a matter of long-established routine that goes on beyond the prime minister’s ken.

All that is wishful thinking. Foreign policy gives prime ministers more freedom from parliamentary scrutiny than domestic policy. Downing Street has been accumulating power over security policy for decades, even more so since the creation of the National Security Council in 2010. The SNP is sympathetic to Mr Corbyn’s views on foreign policy, adopting the toe-curling slogan “bairns [babies] not bombs” and campaigning for the removal of Britain’s nuclear submarines from their base in Scotland. As chancellor, John McDonnell would exercise even more control over domestic policy than Gordon Brown did. That would leave a notably vain prime minister looking for another way of making his mark. The Downing Street bully pulpit would give him the opportunity to opine to the world on things he cares about, such as Israeli foreign policy and Donald Trump’s failures. The next national-security review, due in 2020, offers a chance to revisit questions of hard power, such as Britain’s commitment to spend 2% of GDP on defence.

One-man army

A Corbyn-led government would quickly lead to the biggest change in Britain’s defence posture since the second world war. Even if the country stayed in NATO , as is likely, it would be a passive member, reluctant to push back against Russian expansionism and hostile to the idea of a nuclear deterrent. Given that NATO depends on confidence that it means what it says, this would be a severe blow to its credibility. Britain’s Middle East policy would be revolutionised, with a more hostile stance towards Israel and the Gulf states, particularly Saudi Arabia, and a friendlier one to Iran. America would almost certainly stop sharing critical intelligence with Downing Street, for fear that such secrets would find their way into Russian or Iranian hands. Given Britain’s membership of the Five Eyes intelligence alliance, that would harm Europe’s ability to combat hostile states and non-state actors.

Such a revolution would come at a sensitive time. Mr Trump is already disrupting established security relations (for all their differences, he and Mr Corbyn share a common hostility to the multinational institutions that have kept the peace since 1945). Brexit is straining relations with Britain’s European allies, while gobbling up the political class’s available bandwidth. The Foreign Office is demoralised by decades of cuts, and the security establishment is still tainted by the weapons-of-mass-destruction fiasco. All this is taking place at a time when Mr Putin is on the march and Islamic State is shifting its focus from state-building to global terror. A dangerous world may be about to become more dangerous. ■

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