Today the European Union is wobbling under the weight of problems encouraged in part by that unchecked expansion — stagnant economies, the euro crisis, new pressures from Russia and deep strains over migration, especially from newer members in Central and Eastern Europe.
Having already suffered a “Brexit” vote this year in Britain, Europe faces a series of critical elections in the year ahead. But none is more important than the vote in France, a founding European Union member.
The British decision to quit the European Union was a major blow, but a victory by Ms. Le Pen could be the death knell. And with the election of Donald J. Trump in the United States, that prospect has taken on new weight.
“Donald Trump makes Marine Le Pen sound reasonable,” said François Heisbourg, a special adviser to the Foundation for Strategic Research in France and chairman of the International Institute for Strategic Studies.
“His victory gives her respectability. Everyone knows she’s not Trump — she knows how to use a noun and a verb and is intellectually coherent about what she wants and doesn’t want.”