Arguing that the United States cannot prevent Iran from acquiring nuclear weapons “unless you're prepared to go to war,” syndicated Washington Post columnist and FOX News contributor Charles Krauthammer claimed that multilateral sanctions on Iraq “didn't stop him [Saddam Hussein] in anything.” In fact, Iraq never restarted its nuclear program after the United Nations Security Council imposed sanctions following the 1991 Gulf War, according to the CIA's Iraqi Survey Group (ISG), which led the search for banned weapons in Iraq and documented Saddam's attempts to acquire them.

The ISG's final report, known as the Duelfer report, included among its "Key Findings" in Chapter 2 the observation that “Saddam needed to end UN-imposed sanctions to fulfill his goals” of reconstituting his dormant weapons of mass destruction (WMD) programs:

Throughout the 1990s and up to OIF [the U.S.-led Operation Iraqi Freedom] (March 2003), Saddam focused on one set of objectives: the survival of himself, his Regime, and his legacy. ... Saddam recognized that the reconstitution of Iraqi WMD enhanced both his security and image. Consequently, Saddam needed to end UN-imposed sanctions to fulfill his goals.

[...]

UN sanctions curbed Saddam's ability to import weapons, technology, and expertise into Iraq. Sanctions also limited his ability to finance his military, intelligence, and security forces to deal with his perceived and real external threats.

Chapter 1 of the Duelfer report similarly noted that “Saddam's primary goal from 1991 to 2003 was to have UN sanctions lifted” and that “the starting of any WMD program, conspicuous or otherwise, risked undoing the progress achieved in eroding sanctions.”

In its "Key Findings" on Iraq's nuclear capabilities, the Duelfer report found that Saddam's preparations to eventually restart his nuclear program, which was destroyed in 1991, were contingent on the lifting of sanctions:

As with other WMD areas, Saddam's ambitions in the nuclear area were secondary to his prime objective of ending UN sanctions.

Iraq, especially after the defection of Husayn Kamil [former head of Saddam's WMD program] in 1995, sought to persuade the IAEA that Iraq had met the UN's disarmament requirements so sanctions would be lifted.

ISG found a limited number of post-1995 activities that would have aided the reconstitution of the nuclear weapons program once sanctions were lifted.

From the February 27 edition of FOX Broadcasting Company's FOX News Sunday:

KRAUTHAMMER: I don't see any indication of any will on the part of the Europeans to do anything serious. We would like to be serious on this, but I don't think that we have the actual option. The Iranians know that, and there's nothing that's going to stop them.

There might be an intermediate step if we had European help, as [FOX News Sunday guest Senator John] McCain [R-AZ] indicated, that we end up in the Security Council and pass the sanctions and make Iran a pariah.

But, look, Saddam had sanctions on him as well. It didn't stop him in anything. For a country determined to acquire nukes as Iran is, unless you're prepared to go to war, I don't think there's any indication that we're going to stop them.