Equally, despite its close alliance with President Bashar al-Assad of Syria, Hezbollah appears to have exercised moderation in offering armed support for his regime’s brutal crackdown. While the longstanding relationship between the two makes some assistance almost inevitable, there are no indications that Hezbollah has moved significant arms or personnel Assad’s way.

Europe’s willingness to date to resist U.S. and Israeli pressure to place Hezbollah on its terrorism list and under a sanctions regime has been critical to maintaining the group’s moderation and Lebanon’s uneasy calm. European engagement has provided Hezbollah’s leadership with reassurance that there will be political room for their group in the post-Assad era. This has been key to preventing a pre-emptive offensive by Hezbollah to secure its position, particularly given mounting international pressure against Iran and Syria, its two regional backers.

But European sanctions could change Hezbollah’s strategic calculus in one fell swoop. Coming on the back of the new U.S. sanctions, Hezbollah would immediately feel considerably more threatened, raising the possibility of more violence. This would be devastating for Lebanon and threaten the outbreak of wider conflict that could drag the country into civil war. It would also likely play directly to Assad’s advantage by giving Hezbollah no further reason to chart a middle course. Hezbollah would tie its own survival to that of Assad.

There is no doubt that Hezbollah needs to be held to account for its long history of terrorist activities and unwillingness to submit to the authority of the Lebanese state. European leaders may understandably want to take a stand should Hezbollah be proven complicit in the July killing of six people, including five Israeli tourists, in Bulgaria, but so far these charges are unsubstantiated.

However, it is imperative that European leaders consider the broader ramifications of changing tack on Hezbollah. If they want to protect Lebanon’s fragile peace and prevent Syria’s conflict from spiraling out of regional control, they must show restraint. Of course Europe should continue to raise the issue of Hezbollah maintaining its own militia and support for Assad. But a turn to confrontation may prove counterproductive.