The horrific killing of 12 people who ran the French satirical magazine Charlie Hebdo, which published the controversial Mohammed cartoons in 2011, by suspected Muslim extremists is likely to have serious consequences. In the short run, it will result in shock, grief, and possibly counterattacks on some innocent Muslims living in France. The long-term consequences of the shooting could be monumental.

First, the French could get their first female head of state since Queen Anne’s regency during the minority of Louis XIV. Queen Anne faced a massive revolt of the nobles known as the Fronde and a subsequent civil war. Ms. Marine Le Pen’s presidency could be similarly eventful.

While, as libertarians, we despise much of what Ms. Le Pen stands for, the two mainstream political parties in France, Mr. Sarkozy’s socialist center-right UPM and Mr. Hollande’s Socialist Party, have totally failed to address the legitimate concerns of the French citizens, chief among them the failure of multiculturalism and high unemployment. The country is ready to hand the reins of power to someone else.

Second, the euro will end its role as a global currency and remain a legal tender in something akin to Großdeutschland greater Germany, composed of Germany and her satellites, like the hapless Slovakia. Ms. Le Pen is mistaken in thinking that the French withdrawal from the euro will revive the French economy. French economic difficulties are primarily structural (i.e., high taxes and over-regulation), not monetary.

Be that as it may, Ms. Le Pen has set her sights on exiting the euro and, at least as far as this author is concerned, the sooner she puts the euro out of its misery, the better. They might even build her a statue in Athens. (Perhaps 2,000 years from now, it will be admired with as much reverence as Venus de Milo is revered today, but I digress…).

Third, on day two of a Le Pen presidency, border guards will return to the French frontiers. Of course, the end of the freedom of movement will be in full breach of all sorts of European treaties and conventions. (The British, by the way, would love to do the same, but cannot, because the British, being British, follow the rules. In contrast, the French, being French, will do what they have always done: follow their national interest.)

France will not be stopped. Because as it is big and powerful, it is not subject to the same rules that govern the rest of the EU. That is why the French have been allowed to make mincemeat out of the Maastricht Treaty without any consequences.

That will cause a major crisis in the EU and lead to a clarification of what the EU is–a cooperative arrangement between sovereign states–and what the EU is not–the United States of Europe.