The Senate passed its toughest sanctions to date by a 99-0 vote. Sen. Joe Lieberman had praise for the measure:

This bill represents the most powerful and comprehensive package of Iran sanctions ever passed by Congress. I am grateful to the leadership of Senator Chris Dodd and Congressman Howard Berman for guiding the development of this complex and critically important legislation, as well as the leadership of Senator Reid and Senator McConnell in ensuring its swift passage by the Senate.

I hope and believe that the House will now act swiftly to pass this vital legislation, and that President Obama will sign it into law. Just as importantly, it is critical that these provisions are forcefully and proactively implemented once they become law.

The measures imposed by this legislation—together with sanctions adopted at the UN and, even more importantly, by like-minded nations around the world—offer our last, best hope of peacefully preventing Iran from acquiring a nuclear weapons capability. Time is of the essence.

But Lieberman made clear that sanctions are not an end in themselves. And in contrast to the president’s que sera, sera attitude, Lieberman was emphatic that if the sanctions don’t work (and more about that below), we must use other options, including force:

While we hope that our combined sanctions will change the calculus of the Iranian regime, we must also recognize that every day that passes brings Iran closer to the point of nuclear no return. Ultimately, we must do whatever is necessary to prevent Iran from acquiring a nuclear weapons capability—through peaceful and diplomatic means if we possibly can, but through military force if we absolutely must.

This is precisely what the president and his advisers have refused to say, and indeed have intimated is not in the cards.

But there is another problem. We aren’t likely to know whether sanctions are “working,” and the Iranians are quite likely to exploit the additional time to stave off other measures. How are we to know if work stops on the mullahs’ nuclear programs? And if the Iranians declare that they will return to the bargaining table, what is to prevent them, as they did last year, from practicing the same game of delay as they continue with their plans? The problem, it seems, is not merely the absence of effective tools to force a change in the Iranians’ conduct but also the will and determination to use those tools in a meaningful way.

Obama set the pattern last year — withholding support for the Green movement, muting the reaction to the Qom revelation, and allowing deadline after deadline to pass. From all this the mullahs have learned that very little is required to hold the U.S. at bay and that we are overeager to avoid confrontation. At every turn, they have bested Obama and the “international community” and bought themselves breathing room.

The sanctions, therefore, are not the solution to the Iranian threat. Rather than congratulating the administration for passing sanctions after nearly a year and a half, Congress and pro-Israel groups must make clear that “containment” is not an option and that we will use military force and provide Israel with unconditional support if necessary. “Passed useless sanctions and allowed Iran to go nuclear” is not a result from which the president, lawmakers, or American Jewry will recover. And it is not an outcome Israelis can tolerate.