The failure of the UN and Arab League monitoring mission to bring an end to Assad's killing machine has forced the international community to face the Syrian challenge head-on. Western governments can no longer sit back and wait for Arab monitors to watch the killing continue without also incurring some of the blame. The Obama administration has taken the right steps by withdrawing the U.S. diplomatic mission to Syria and by supporting the establishment of an international coalition of "friends of Syria"-two measures I've been advocating for some time. But as Syria enters an even more brutal phase in the conflict between its ruler and ruled, stronger measures are needed.

Some now argue for arming the opposition, while others go further and call for an immediate military intervention by Turkey, a coalition of Arab states, and perhaps NATO forces. Such steps may be necessary. But they also risk making the situation worse rather than better. To be sure, they should not be taken off the table, if only to bolster the efficacy of other non-lethal efforts, including intensifying sanctions, isolating Assad and his top supporters, and trying to split the military off from Assad. The problem with all of these options is that they will take time during which more Syrians will surely die. Such options should be explored, and the use of force should not be completely ruled out-which is how the Obama administration is proceeding.

But other more immediate steps must be explored that could end the bloodshed in Syria. One approach would be to try and engage, rather than further vilify, the Russians. Foreign Minister Lavrov, during his Damascus visit, put forward a plan that would entail talks between Assad and the opposition. This approach, however morally repugnant, is simply not workable. With some seven thousand Syrians dead so far, Mr. Assad has dealt himself out of the game as an interlocutor that can be considered credible either by the international community or by Syrian oppositionists. Only Moscow seems to view Assad as credible. Clearly, for the bloodletting to end, Assad must step down, as the Arab League has suggested. This could then pave the way for dialogue and an end to the bloodshed.

But it is surely worth trying to come to a grand bargain with Russia over Syria. Under such an approach, Moscow would be enlisted to use its clout and influence to get the Syrians to stop the killing, withdraw its army from population centers, and to bring about Mr. Assad's immediate departure from Syria. As an enticement, the West should be willing to consider sanctions relief in return for such an end to the bloodshed and Assad's departure. Such an approach would allow Russia to repair its fractured relationship that has isolated it from an Arab world that now identifies Moscow as an enemy of the Arab uprisings and as a supporter of the forces of repression. It would also provide an opportunity for the United States and Russia to work cooperatively on a common problem.