You could say that Europe has crises enough without worrying too much about a Hungarian dissident turned petty tyrant. Hungary, after all, is not even a member of the euro. To overlook Viktor Orban's journey from anti-communist progressive to populist xenophobe would, however, be to repeat a mistake made about Greece. The troubles of Europe's small powers can be a harbinger of bigger dangers around the corner.

Hungary's prime minister presents a reminder - should anyone on this continent need one - of the familiar trajectory from economic chaos to political authoritarianism. The European Union has had two grand projects since the fall of the Berlin Wall: the single currency and the advance of democracy eastwards. The euro is now in serious trouble. Mr Orban sends a powerful message about the perils facing democracy.

This week saw the introduction of Mr Orban's new constitution. Suffused with ethnic nationalism, it reeks of an ambition for one-party rule. It promises repression of personal freedoms within Hungary and, through an extension of citizenship to Hungarian minorities elsewhere, threatens instability in ethnically-diverse neighbours.

The constitution has to be seen alongside a slew of new basic laws and the gerrymandering of the electoral system. Together, they bestow inordinate power on the ruling Fidesz party. The prime minister can claim to have won the 2010 election fairly. Now he is deploying a two-thirds majority in parliament to deny opponents the same possibility.

David Fuller's view The Eurozone crisis is not just about a half completed currency union among 17 member states and a sovereign debt crisis. A strong Western Europe is needed to resume and sustain the process of democratisation in Eastern Europe.