SCRATCH your head and the memory flickers into life. Britain was once an influential member of the European Union. Its politicians were infuriating but effective, its diplomats skilled at crafting alliances, its officials adept at the push-me-pull-you of shaping EU law. This is how Britain earned a budget rebate, an opt-out from the euro, and, under David Cameron, a “renegotiation” of its membership (since voided by the Brexit vote). Nor were its energies devoted solely to carving out special treatment. Vital EU achievements like the single market and post-1989 enlargement owe their existence to dogged British diplomacy.

How things change. British officials describe a chill that set in the moment voters elected to leave. Ostensibly Britain remains fully signed up to the EU, with voting rights, representation and all the paraphernalia of membership. In reality, its influence has largely evaporated. That has a potent effect on the remaining 27 members. “The balance of power is changing every day,” says a diplomat from a country friendly to Britain. “You can feel it.” Almost 18 months before Britain is due to leave, Brexit is changing the EU in a way that unsettles some, inspires others and affects all.

Few countries wanted Britain to leave, but for some the stakes are especially high. Assembling compromises inside the EU is a delicate dance often dominated by the positions of a few big beasts. Like-minded countries were delighted to rally behind the British on matters like trade, regulation and the single market. Smaller governments often appreciated Britain blocking Franco-German stitch-ups. Now few care to hear the views of a country that has one foot out of the door, and few British officials seek the opprobrium they would attract if they offered them.

Take trade, where fresh fault-lines are emerging. Countries like the Netherlands, Denmark and even Spain are casting a suspicious eye on Emmanuel Macron, France’s president, whose calls for a “Europe that protects” are starting to sound a little like protectionism. At a recent summit Mark Rutte, the Dutch prime minister, questioned Mr Macron’s attempts to slow down EU trade talks with Mercosur, a Latin American bloc; in the past, say Dutch officials, they might have left it to Britain to take on the French. On the increasingly modish topic of “trade remedies” (anti-dumping measures, investment screening and so on), the absence of a sceptical British voice also tilts the scales against the free-traders.

Low-tax economies like Ireland and Luxembourg fear a fresh Franco-German assault on their fiscal independence, another issue on which they could once rely on stout British resistance. The European Commission has already announced that it wants to remove governments’ rights to veto EU tax proposals. On foreign policy, the EU’s carefully co-ordinated sanctions on Russia over its incursions in Ukraine may have been shepherded by Angela Merkel but were energised by a group of hardliners led by Britain. The measures must be rolled over every six months; Britain’s departure could hasten their eventual end. Fellow Russia hawks, like the Baltic states, worry about what Brexit will mean for the EU’s ability to stand up to bullies.

But others spot opportunities created by the departure of the irascible Brits. Grand federalist schemes, such as replacing the British contingent of European parliamentarians with transnational lists presented to all EU voters, will go nowhere (for now). But Brexit has also inspired those who never liked the model of endless exceptionalism pioneered by Britain but welcomed by many others. On the single currency, for example, Britain’s presence once served as a reassuring reminder to countries outside the euro zone that they could not be sidelined. Now the commission is quietly reminding euro “outs” that most of them have a legal obligation to join.

Yet Britain’s departure also forces some tricky questions on the rest of the EU. British governments used to veto anything that even sniffed of defence co-operation inside the EU, for example, claiming it would undermine NATO. Now it is back on the table: Mr Macron wants other countries to share France’s military burdens in the Sahel and the commission wants a bigger common defence fund. Brexit calls the bluff of leaders who said discussing such issues was useless while Britain was in the room. The loss of one of the two members, along with France, with genuine military clout should also trigger concern over the EU slipping into geopolitical irrelevance. But are Europe’s defence shirkers really prepared to pull their weight now that Britain is on the way out? A summit in December will test the water.

Future imperfect

It is harder still to predict the long-term implications of Brexit for the EU. Immediately after last year’s referendum some of the more gung-ho Brexiteers argued that the example of Britain’s departure would inspire floods of imitators. A series of electoral setbacks for anti-Europeans over the past year has killed off that idea for now. Perhaps these prophecies will eventually be fulfilled if Britain manages to make a success of life outside the club, although the chaotic process of Brexit seems to have given the EU’s popularity a bump everywhere else. A more plausible outcome, gently entertained by Mr Macron, is that over time the EU adopts a more flexible model of membership, reassembling itself into “tiers” that allow countries to choose the level of integration to which they are best suited.

Such notions, notes a disinterested British official, run up against the centripetal forces that drive many EU countries to remain as close to the core as possible. At present it suits everyone in Europe to treat Brexit as a sui generis case from which no broader lessons can be drawn. Perhaps that is right. But it should not preclude creative ideas that can accommodate a variety of preferences, including an outer tier for laggards, stragglers and those countries that simply seek a looser relationship with the EU. Perhaps it might even one day find room for Britain.