Announced at a joint press appearance by Secretary of State Hillary Clinton and Treasury Secretary Timothy Geithner, the new sanctions include a ban on travel to the U.S. and a freeze on any U.S.-based assets owned by the officials, mainly top officers in the Iranian Revolutionary Guard Corps (IRGC), including its commander, Mohammad Ali Jafari. 

"On these officials' watch or under their command, Iranian citizens have been arbitrarily beaten, tortured, raped, blackmailed and killed," declared Clinton. 

"Yet the Iranian government has ignored repeated calls from the international community to end these abuses, to hold to account those responsible, and respect the rights and fundamental freedoms of its citizens," she added. 

The sanctions are the first imposed by Washington against Iranian officials for rights-related reasons. They come amid growing speculation over the resumption of negotiations between the U.S., as well as other major powers, and Tehran over the latter's nuclear programme, and amid increasing calls by Israel-centred neo-conservatives, among others, for the Obama administration to take military action if such negotiations do not soon bear fruit. 

In a speech before the influential Council on Foreign Relations (CFR) Wednesday, Independent Democratic Sen. Joseph Lieberman praised the new sanctions, as well as the administration's success in getting its European and Asian allies to impose tough economic sanctions of their own. 

But he also called for the administration to "take steps that make clear that if diplomatic and economic strategies continue to fail to change Iran's nuclear policies, a military strike is not just a remote possibility in the abstract, but a real and credible alternative policy that we and our allies are ready to exercise." 

"(N)othing is more corrosive to the prospect of resolving this confrontation peacefully than the suspicion—among friends and enemies alike in the Middle East—that in the end, we will acquiesce to Iran's acquisition of a nuclear weapons capability," the former Democratic vice-presidential candidate declared. "If a nuclear Iran is as unacceptable as we all say it is, we must be prepared to do whatever is necessary to prevent the unacceptable." 

Lieberman's speech, in which he also described "stopping Iran from acquiring nuclear weapons capability" as "the single most important test of American power in the Middle East today," was the latest in a series by key figures here arguing in favour of military action if sanctions and diplomatic efforts fail to curb Iran's nuclear programme. 

Last week, for example, Republican Sen. Lindsey Graham, with whom Lieberman has frequently aligned himself, also said Washington must prepare itself to use military force to prevent Iran from actually obtaining a weapon. 

"If you use military force against Iran, you've opened up Pandora's box," Graham told a hawkish audience at the American Enterprise Institute (AEI), a neo-conservative think tank that played a key role in the run-up to the 2003 invasion of Iraq. "If you allow Iran to get nuclear weapons, you've emptied Pandora's box." 

"I'd rather open Pandora's box than empty it," said Graham, who also predicted that "a military strike by air and sea" could result in the overthrow of the Iranian regime without the need for U.S. ground troops. 

Shortly after Graham's comments, Israel's U.S.-born and - bred ambassador, Michael Oren, strongly suggested in a Yom Kippur sermon to three influential Washington synagogues that Israel would attack Iran on its own if Obama did not do so – a message that was immediately and explicitly endorsed by the editor of the Weekly Standard and a major Iraq war hawk, William Kristol, who also previewed
Lieberman's speech on the Standard's website Tuesday night, noting approvingly that it "should cause quite a stir". 

The new sanctions, which are far more narrowly targeted than sweeping economic sanctions against foreign companies doing business with Iran enacted by Congress in June, were authorised by an amendment submitted by Lieberman and Republican Sen. John McCain to the Comprehensive Iran Sanctions, Accountability, and Divestment Act of 2010. 

Obama had been heavily criticised by Republicans and many human rights activists after the contested June 2009 presidential election for not speaking out more forcefully against what many here believe was a fraudulent result and for the subsequent efforts to suppress the opposition Green Movement and its supporters. 

The administration's reluctance to do so was explained in part by the priority Obama placed on engaging Iran diplomatically - along with the other four permanent members of the U.N. Security Council plus Germany, or the "P5+1" - in hopes of reaching an agreement that would persuade Tehran to abandon or drastically curb its nuclear programme. 

The administration feared that adopting the Green Movement's charges of fraud, or criticising the human rights record of President Mahmoud Ahmadinejad too harshly would make it harder for his government to engage or, worse, trigger a nationalist backlash that would strengthen hard-line elements within the regime. 

"(W)e …were very mindful of the messages we were getting from Iranians both inside Iran and outside Iran that we had to be careful that this indigenous opposition …was not somehow seen as a U.S. enterprise," Clinton said Wednesday. 

But as the repression against the Green Movement intensified and after Tehran equivocated over a confidence-building proposal put forward by the P5+1 last fall that would have sent half of Iran's growing stockpile of low-enriched uranium out of the country in exchange for more highly enriched fuel for a nuclear plant that produces medical isotopes, the administration became less restrained in its criticism.

In one statement that drew widespread notice and approval among hawks and some human rights activists here last February, Clinton accused the regime of "moving toward a military dictatorship". 

That assessment coincided with the administration's decision to lobby other key countries, notably Russia and China, to impose a fourth round of U.N. Security Council sanctions against Iran – a watered-down version of which it succeeded in getting last June; support Congress' enactment of sweeping unilateral economic sanctions against third-country companies doing business with Iran in key sectors; and to lobby its allies to adopt similar measures. 

The impact of those sanctions – and whether they will succeed in persuading Iran to accept curbs on its nuclear programme – is a matter of fierce debate here. 

While Ahmadinejad has denounced them, as he did at the U.N. last week, as "meaningless", other officials, notably former President Akbar Hashemi Rafsanjani, have urged the government to take them seriously. 

Administration officials have suggested that Ahmadinejad's prediction last week that negotiations between Iran and the P5+1 will likely resume next month indicates that the sanctions are having the desired effect. 

The impact, if any, of the sanctions announced Wednesday on prospects for those negotiations is unclear, but Clinton extolled them as a "new tool that allows us to designate individual Iranians, officials complicit in serious human rights violations, and do so in a way that does not in any way impact on the well-being of the Iranian people themselves." 

*Jim Lobe's blog on U.S. foreign policy can be read at http://www.lobelog.com.