This week's installment of Behind the Lines covers Iran's role in Afghanistan and Pakistan with Hillary Mann Leverett, a former National Security Council official and co-author of The Race for Iran.

1. In late May, then-top commander General Stanley McChrystal said there is "clear evidence of Iranian activity" in training and providing weaponry to the Taliban in Afghanistan. What are Iran's core interests in Afghanistan, and how have they evolved in the last nine years? How do those complement or work against what the U.S. and NATO are trying to achieve there?

Iran has a strategic stake in Afghanistan that has not changed in the last nine years. Tehran's overriding interest is to prevent Afghanistan (with its long and lawless border with Iran) from being used as a platform from which to attack or undermine the Islamic Republic or to weaken Iran's standing as a regional power. 

To prevent Afghanistan from being used as an anti-Iranian platform, the Islamic Republic has worked, over many years, to form relationships with Afghan players who could keep Iran's Afghan enemies (principally the Taliban but also other anti-Shiite and anti-Persian groups) and their external supporters (principally Saudi Arabia and Pakistan, two of Iran's most important regional antagonists) in check. To this end, Iran has worked to strengthen and unite Afghanistan's Shiite Hazara and other Dari/Persian-speaking communities (which together comprise about 45 percent of the population) as a counterweight to anti-Iranian, pro-Saudi, and pro-Pakistani elements among Afghan Pashtuns (roughly 42 percent of the population). The Hazara and other Dari/Persian-speaking communities were, of course, the core of the Northern Alliance that fought the Taliban during the 1990s, and were supported by India and Russia as well as Iran.

In contrast to Iraq, where Shia are a clear majority of the population and Shiite groups linked to Tehran are the most important political forces in the country, Iran knows from bitter experience that the Hazara and the other Dari/Persian-speaking communities provide, at best, inadequate protection for Iranian interests in Afghanistan, because they cannot govern the country in a way that keeps it relatively stable and minimizes Pakistani and Saudi influence. So, alongside its alliances with the Hazara and the other Dari/Persian-speaking groups, Iran has also cultivated ties to some Pashtun elements in Afghanistan and supported the country's Pashtun President, Hamid Karzai.

As part of its cultivation of ties to Pashtun elements, Iran has almost certainly reached out to some Taliban factions. But I would wager a substantial sum that America's "ally" Pakistan is providing vastly more support to the Afghan Taliban than anything the Islamic Republic might be doing. And Tehran remains strongly opposed to the Taliban's resurgence as a major force in Afghan politics, for two reasons. First, the Taliban have traditionally persecuted Iran's Afghan allies -- especially the Shia Hazara -- and have even murdered Iranian diplomats. Second, Tehran sees the Taliban as a pawn for the expansion of Pakistani and Saudi influence in Afghanistan.   

As Tehran pursues this strategy of multiple alliances within Afghanistan, it must also assess the evolving role of the United States there and the implications of the U.S. posture toward Iran for Iran's Afghanistan policy. If the United States and NATO could convince Iran that they want an independent and stable Afghanistan that would be friendly to Iran, then U.S./NATO and Iranian strategies and tactics could complement each other very constructively. (This was very much the case in the months following the September 11, 2001 terrorist attacks in the United States, when I was one of a small number of U.S. officials engaged in ongoing discussions with Iranian counterparts about how to deal with Afghanistan and al-Qaeda, and U.S. and Iranian policies regarding these issues were rather closely coordinated.)

But, if Tehran perceives Washington as hostile to its interests -- which, unfortunately, is currently the case, given the Obama administration's drive to impose sanctions and continued use of covert operations to undermine the Islamic Republic -- then Iranian policymakers will regard the United States, along with America's Pakistani and Saudi allies, as part of the complex of anti-Iranian external players that Iran needs to balance against in Afghanistan. In this context, Iran has a strong interest in preventing U.S. troops in Afghanistan from being used to attack Iran directly, used as covert operatives to undermine the Iranian government, or used to strengthen Iran's regional rivals.

2. What is Iran's likely reaction to the expected U.S. drawdown in Afghanistan, scheduled to begin in July 2011? How might Iran react if the Taliban's influence across Afghanistan grew, particularly in Herat and other border provinces?

In contrast to the United States, which seems at least to be looking for a viable exit strategy from Afghanistan, there is no exit strategy for Iran. Iran publicly calls for the withdrawal of U.S. troops from Afghanistan, partly because U.S. forces there could be used against Iran. But Tehran also calls for the withdrawal of U.S. troops from Afghanistan because Iranian policymakers believe that the extended U.S. presence there is seen by much of the population as an occupation and that it is this occupation which is fueling an increasingly fierce cycle of violence and instability. From Tehran's perspective, this cycle of violence and instability empowers Iran's Afghan adversaries, principally the Taliban, and their external backers, Pakistan and Saudi Arabia, both of which are regional rivals to the Islamic Republic.

For an Iranian standpoint, the most constructive American strategy would have been for the United States to begin a gradual but steady withdrawal of troops a few years ago when that could have helped shape a political settlement based on power sharing among all of Afghanistan's major constituencies. From an Iranian perspective, such a settlement could have included the Pashtun, though, at least at the time, not necessarily the Taliban, and would have given Iran's Afghan allies -- who, at the time, were also America's allies -- the upper hand. Today, Iran is concerned that, as America belatedly positions itself to begin withdrawing forces from Afghanistan next year, the Obama administration still has no coherent strategy regarding President Karzai's drive for a political deal -- a deal which, because of mistakes made by Washington, must now include the Taliban and its chief external backers, Pakistan and Saudi Arabia.

In the political and security vacuum that is today's Afghanistan, Karzai's effort to engage the Taliban is generating deep unease among Iran's allies in Afghanistan's Tajik, Uzbek and Hazara communities. Already, the leadership of these non-Pashtun communities -- who also dominate the upper echelons of the Afghan military -- are organizing to resist, by force, any serious attempt at power-sharing between Karzai's government and the Taliban. If the Taliban's political influence across Afghanistan continues to grow -- particularly in an environment conditioned by what Tehran sees as America's strategic and tactical incompetence -- Iran will support its Afghan allies as they "push back" against a resurgent Taliban. 

3.   It's been reported that Pakistan is seeking to increase its leverage in Afghan reconciliation talks. What might Iran's reaction be to an increase in Pakistani influence in Afghanistan?

Iran is concerned that the United States' interest in fostering sufficient stability in Afghanistan for long enough to allow U.S. troops to begin leaving next year will lead Washington to drop the "red lines" it has imposed on Taliban participation in a political process. Iran is concerned that Pakistan and Saudi Arabia will be able to use the Taliban's unchecked involvement in a power-sharing arrangement as a proxy to expand their influence in Afghanistan at Tehran's expense and to threaten the Islamic Republic.

Under these circumstances, Iran will intensify its support for key players among the Hazara, Tajik, and Uzbek groups, just as it did during the civil war that broke out after the Soviet withdrawal from Afghanistan and after the Taliban took power in Kabul in 1996. These dynamics raise the risks of renewed civil war in Afghanistan -- a civil war that would simultaneously be a proxy war among Iran, Pakistan, and Saudi Arabia, the country's most powerful external players. These were precisely the conditions under which al-Qaeda found sanctuary and thrived in Afghanistan during the 1990s. 

4.   How would the ‘grand bargain' between the U.S. and Iran affect stability in Afghanistan and Pakistan?

Post-conflict stabilization in Afghanistan requires recognizing and working with the integral connections between Afghanistan's internal balance of power and the broader balance of power among major states in the Middle East, Central Asia, and South Asia. And that means cooperation with Iran is essential to stabilizing Afghanistan and, by extension, Pakistan.

Following 9/11, Iran worked with the United States on the short-term project of overthrowing the Taliban -- but with the long-term goal of prompting Washington to reconsider its hostile posture toward the Islamic Republic. In effect, the Iranians hoped that cooperation with the United States would facilitate a U.S.-Iranian "grand bargain" -- but this approach did not work, largely because of American resistance to a broader opening to Iran.  

Under current circumstances, Iran would need to be persuaded to cooperate once again with the United States in Afghanistan -- persuaded, in particular, that power-sharing could be done in a manner that addressed Tehran's longstanding concerns about the Taliban, the regional balance of power, and U.S. intentions toward the Islamic Republic. This cannot be done while Washington is pursuing sanctions against Iran -- however feckless they may be -- and offering progressively less veiled support for regime change in Tehran. Today, cooperation with Iran on post-conflict stabilization in Afghanistan has to be embedded in a broader strategic understanding between the United States and the Islamic Republic -- what my husband, Flynt Leverett, and I have described as a U.S.-Iranian "grand bargain".

So, in other words, a U.S.-Iranian grand bargain has become essential to avoiding something close to strategic failure in Afghanistan. The Islamic Republic will, as I described, continue supporting its longstanding Afghan allies in resisting a Taliban onslaught backed by Pakistan and Saudi Arabia. But, in the absence of a broader strategic understanding, those efforts will be seen, in Washington, and elsewhere, as undermining whatever political arrangements the Karzai government has reached with the Taliban. And that will fuel a regional proxy conflict with Afghanistan as the main battlefield, and with the United States drawn increasingly into supporting Pakistan and Saudi Arabia. That is a position the United States has been in before. We should not want to go there again.

Hillary Mann Leverett, CEO of the political risk consultancy STRATEGA, is a former official with the National Security Council, State Department, and the U.S. mission to the United Nations. She blogs at the Race for Iran.