EUROPEAN VOTERS have delivered a powerful if not unsurprising rebuff to the austerity policies that have caused misery around the continent while failing to remedy its currency and debt crises. In France on Sunday, voters rejected President Nicolas Sarkozy’s bid for a second term, replacing him with Socialist Francois Hollande. In Greece, meanwhile, both centrist parties were punished in favor of extremists on the right and left, including neo-Nazis. The result will be demands by France and an alliance of southern European countries for a revision of the fiscal pact that requires most European countries to dramatically reduce spending or raise taxes, and an insistence by Greece that the terms of its bailout be eased.

In one respect, this is not bad news. As most economists have recognized, the tough austerity diet has failed to significantly reduce debts or revive investor confidence in Greece, Spain and other ailing European Union members. Even German Chancellor Angela Merkel now acknowledges that some kind of “growth pact” is needed to give hope of recovery. When Mr. Hollande takes office later this month, an opportunity would seemingly open to negotiate one that splits the difference between the austere German and expansive French agendas.

Unfortunately, an accord is unlikely to be so simple. Ms. Merkel’s view of a growth pact is that it should concentrate on structural reforms, such as those Germany undertook a decade ago, that would liberalize labor markets and trim unsustainable social programs. Mr. Hollande has shown no interest in such reforms and instead champions an unworkable tax-and-spend formula. His immediate plans in France include raising the top income tax to 75 percent, lowering the retirement age for some workers from 62 to 60, and hiring 60,000 teachers.

Still, Mr. Hollande is no radical, and Ms. Merkel is deeply committed to preserving the European Union and euro currency. So it’s possible to imagine a muddle-through in which debtor countries commit to structural reforms in exchange for measures like greater E.U. investments in infrastructure projects. What might help most is a willingness by Germany and other creditworthy countries to spend more themselves, which would create demand for imports and encourage price adjustments that would make southern countries more competitive.

Even if a new union-wide compact can be worked out, Europe will still face two big threats. One is the worsening turmoil in Greece, which appears unlikely to produce a government willing or able to comply with the current bailout agreement. As it is, Greece has largely failed to implement significant economic reforms, and its international overseers would be right to conclude that without them there would be no purpose to easing the bailout terms. Perhaps Greeks soon will be pushed into another election, but a default and exit from the euro may end up being the only way forward.

The surge of extremist parties in Athens, meanwhile, has underlined a growing political threat to the European status quo. In France, 30 percent of presidential votes in the first round went to the fringe; in Germany a “pirate party” is gaining strength. What most of the outsiders have in common is a rejection of a union based on a common currency and relative openness to trade and immigration. That swelling and toxic sentiment makes it only more urgent that E.U. leaders plot a credible path to economic revival.