French military strikes in Syria are an understandable reaction to the killings in Paris, but they will not diminish the threat from ISIS and could make it worse.

As Andrew Bacevich reminds us, the United States and its partners have been waging war against terrorism for decades, killing tens of thousands of people in Afghanistan, Iraq and other countries, but the extremist threat continues to grow, aroused in part by our attacks. Military strikes from the West are exactly what the militants want, providing fodder for recruitment and justifying what is otherwise unjustifiable. Will we fall into that trap again?

Air strikes cannot defeat terrorism, and a ground invasion of Syria or Iraq would be unacceptable politically and unsustainable militarily. A more realistic and effective response is needed to counter the growing ISIS threat.

Instead of pursuing the illusion of military solutions, France should join with the United States and other countries to assemble a powerful global coalition to impose tougher UN sanctions. The immediate goal should be to further isolate and weaken ISIS and cut off its vital sources of finance and supply. Greater efforts are also needed to address the underlying grievances and conditions that generate violent extremism.

If there is to be ‘war’ against ISIS (in the figurative sense), the United States, France and other countries must bring this struggle to the U.N. Security Council and mount a massive international campaign that is commensurate with the threat. Russia and China are on board with this agenda and will more readily cooperate if the mission is authorized through the UN.

The Security Council has imposed some initial sanctions against ISIS, but these measures have not been effectively implemented. Tougher resolutions are needed to enforce compliance with existing sanctions and establish greater authority for stronger measures.

A concerted effort is also needed to shut down the cyber-jihad ISIS and its supporters are waging on the Internet.

Why do we allow these groups to continue using social media to glorify violence, spread hatred and recruit terrorists? This is a challenge that no state can solve on its own, where an international response under a UN mandate is urgently needed.

Many other steps can be taken to undermine ISIS and reduce the threat of extremism: more vigorous diplomatic efforts to achieve a ceasefire and political solution in Syria and political power sharing arrangements in Iraq; increased funding for the millions of refugees who have been forced to flee the conflict; sustained support for peacebuilding and development programs in the Middle East and among refugee populations in the West to address the underlying conditions that give rise to terrorism. All are approaches uniquely suited to UN involvement.

The U.N. was created 70 years ago to address threats to international peace and security. Let’s use the world body now to counter the clear and present danger posed by ISIS.

The proposed steps will not bring immediate results, but concerted international action can strengthen the fight against violent extremism and will avoid the harmful blowback effects that will almost certainly result from more military action.

Nuclear policy and sanctions expert David Cortright is director of policy studies at the University of Notre Dame’s Kroc Institute for International Peace Studies.