Unfortunately, then for Trump, a long-time anglophile who has talked with such delight about plans for a presidential sleep-over at Buckingham Palace later this year, U.S. security interests will require Washington to shun the Corbyn-led British in a crisis and adopt a new policy of “France first.” Freedom fries, anyone?

Meanwhile, one can only imagine what the Kremlin would think about a Prime Minister Corbyn. The damage already done to NATO’s credibility and deterrence by Trump’s reluctance to reaffirm the core collective security commitment in the NATO Treaty, Article V, is bad enough. But the damage to NATO’s solidarity and cohesion posed by Corbyn leading Britain is beyond Moscow’s imaginings. Russia has been working to drive wedges between key members of the trans-Atlantic alliance since the height of the Cold War.

In Corbyn, Russia would have the ultimate “useful idiot” – a leader of a top NATO government who genuinely believes the alliance should not exist, who blames NATO for tensions with Russia, and who has said he would never follow NATO’s strategy of nuclear deterrence. Kremlin operatives would probably feel like they hit the “power ball” jackpot in a geopolitical lottery.