Were the Russians to follow through on this threat, the consequences would indeed be serious since Lithuania is a member of Nato. Any armed action against the country would be met with an Article 5 response under the agreement that an attack on one member is an attack on all. A war that has become a proxy confrontation between the West and Russia would become a real one. Kaliningrad is especially important for Russia because it is where its Baltic fleet is headquartered and its reliance on rail transit through Lithuania has always been a potential flashpoint. The ban covers some 50 per cent of the items that Kaliningrad imports and includes coal, metals, construction materials and advanced technology. The secretary of Russia’s Security Council warned that, unless the restraints were lifted, “appropriate measures” would be taken and would have “a serious negative impact on the population of Lithuania”. This sounds like braggadocio but it cannot be lightly dismissed. Nato needs to be ready for what could be a serious escalation of the crisis.