America’s plan for withdrawal from Afghanistan had a fatal flaw – the sudden closure of the Bagram Air Base. It was from there that United States air, logistical and technical support was provided to the Afghan forces, without which they were severely crippled in their battles with the Taliban. The closure of the base was ordered without consultation either with the Afghan military or with America’s Nato allies in the field, including Britain, and carried out without prior announcement.

In so doing, the US has placed a doubt in the minds of its allies. It suggests that the fundamental priority in Washington is not just America First but America Alone. In practice the United Kingdom was always likely to play junior partner to its much bigger best friend, but the Afghanistan experience suggests this “special relationship” carries no useful leverage.