French President François Hollande’s trip to Baghdad today to shore up support at home for expanded Western strikes against Islamic State militants leaves him vulnerable to criticism that he is cozying up too closely to US interests. Many of the European leaders who followed the US to war in Iraq a decade ago were punished at the polls.

But this time, he and his European counterparts say they have a much stronger argument in favor of intervention in the Middle East: their safety depends on it.

Hundreds of Europeans, many of them from middle-class families, have left their homes to join the extremist factions in Syria and Iraq, as The Christian Science Monitor profiled in a recent in-depth report.

Hundreds of them have easily returned back home with European passports, and leaders say their presence is now the biggest security threat the region faces.

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The French were reminded of the threat when a French journalist who was held hostage in Syria said last week that one of his captors was a Frenchman suspected of a recent attack on European soil.

As the Monitor reported earlier:

The European Union’s counterterrorism coordinator, Gilles de Kerchove, says the deadly shooting of four people at a Jewish museum in Brussels in May at the hands of a suspected French jihadi who’d been in Syria underscores the danger. “[Governments] rank this foreign fighter phenomenon as their No. 1 concern for internal security,” he says.

The beheading of American journalist James Foley, whose executioner spoke English with a British accent, had a similar shock effect for Britain and the rest of Europe.

At a press conference today in Iraq with President Fouad Massoum, Hollande said that the IS militants are waging war on “all people who do not share their vision or ideas."

His words come as Germany banned flags and other symbols that stand for the Islamic State. German Interior Minister Thomas de Maiziere said radical groups, which have successfully recruited some 400 German nationals, pose a threat to German towns and cities.

“More than 100 Islamists have returned. Many frustrated, but others with combat experience. They have learned to hate and kill," Mr. de Maizière told reporters today. "They are well connected. They have been well trained to fight and are possibly willing to share their knowledge with other supporters and recruit new supporters. We must prevent radical Islamists from bringing their Jihad into our cities.”

Muslim radicals made news this week in Germany when a patrol of "Shariah Police," as they labeled themselves on the back of their vests, roamed the streets of the city of Wuppertal to “police” the drinking of alcohol.

Germany has said that it won't join US-led airstrikes. France has said it would do so in Iraq, but only with the approval of the Iraqi government. It remains unclear if it would participate in Syria, since France is sensitive to anything that would bolster the Syrian government's hand. Hollande holds an international conference on the crisis Monday.

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No government in the region, however, can easily dismiss this as a "far-away" threat.

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