As the European project grew from six reasonably cohesive members to 28 more diverse and less controllable ones, it was faced with two big questions. One was what to do if a country decided to leave. The response of the United States to South Carolina’s secession in 1860 seemed excessive, so instead the treaty was amended to include Article 50, which sets out the procedure for exit. The hope was that it would never be used, but now Britain is invoking it. Untried though the procedure is, one thing seems certain: it will be long-drawn-out and painful for everyone. The second question was what to do if a country started to trample on the democratic standards that are a condition of membership. Europe has had to consider this issue before, in 2000, when Austria brought Jörg Haider, a far-right politician, into a coalition government. The EU tried to isolate Austria by freezing contacts, but when that failed to oust Mr Haider it gradually thawed, and has since tacitly accepted governments sustained by extremist parties. In the 2000s several commentators suggested that Italy under Silvio Berlusconi would have failed the Copenhagen criteria for membership because he wielded such enormous power over the Italian media, but at the time nothing was done about it.