Pakistani President Asif Ali Zardari paid a second visit to Tehran last weekend after having been there only three weeks ago. Various speculations have come out as to what may have motivated Zardari to pay two official visits to Tehran within just three weeks. Official reports by Pakistani and Iranian sources broadly characterized the visit as “part of the on-going process to strengthen bilateral ties, step up consultations with countries in the region for peace and stability at a time when tension was developing in some parts and for promoting peace and stability in Afghanistan and fighting militancy.” But this rationale hardly warrants two official visits at the level of head of state in such a short span of time. After all, such concerns could be dealt with by lower-level officials as in the past.

Some other speculations presented around the web seem too farfetched to merit any serious scrutiny. Playing a mediating role between Iran and the West, while Pakistan itself is currently embroiled in a crisis with the United States, or acting as a mediator between Saudi Arabia and Iran, while the tensions between the two countries have largely subsided and while the two parties themselves can discuss their problems directly or, if needed, lower-level third party actors can do the task, are among such speculations made around Zardari’s recent visit to Tehran.

In light of recent developments in Pakistan’s foreign policy, it seems more plausible to think that, more than any other factors, Zardari’s last two visits to Tehran are explained by the unfolding political crisis between Pakistan and the United States, which was provoked by the U.S. raid on Osama bin Laden’s hideout near Islamabad in early May, drawing Pakistan’s strong condemnation as a blatant violation of its national sovereignty. The fallout from the raid including Pakistan’s decision to restrict access of the U.S. military to its soil for conducting drone strikes on suspected militants and reducing the number of American military advisors in Pakistan and the recent U.S. decision to freeze $800 million worth of military aid to Islamabad have provided further incentives for Pakistan to seek or make the impression of seeking closer partnership with its Western neighbor.

Given the recent history of tensions in U.S-Pakistan relations, the question poses itself as to what the recent apparent warm-up in Iran-Pakistan relations signify and what its implications might be for U.S. interests in the region? To begin with, it should be noted that even in the absence of a crisis in U.S-Pakistan relations, Iran and Pakistan have abundant rationales for establishing a dependable framework for closer bilateral relations. Without going into detail, it is clear that apart from cultural and religious bonds between the two nations, economic and security considerations are the driving force behind the relations of the two countries.

Due to conflict of interests between the two countries in certain policy areas in the past, they have not been able to fully realize their potentials in forging a strategic partnership with each other. Their divergent foreign policies towards Afghanistan have long been a major source of tensions between the two countries. These tensions were at their peak in the second half of the 1990s when the Taliban had captured most parts of Afghanistan. While Pakistan had lent its full support to the Taliban, Iran was at odds with the group and had instead given its weight to the Northern Alliance forces, a coalition of Persian-speaking and other non-Pashtun ethnic groups in Afghanistan. While creating a host of other problems, the U.S. invasion of Afghanistan and the overthrow of the Taliban regime put an end to the proxy wars between different regional powers in Afghanistan and subsequently removed a source of tension in the relations between Iran and Pakistan, at least on a temporary basis.

Both Pakistan and Iran have also needed to balance their relations with each other against their interests in cultivating friendly relations with the regional rivals of each other. Iran has attached importance to its relations with India and has not wished its relations with Pakistan to come at the cost of alienating India. Similarly, Pakistan maintains important economic interests in its relations with Iran’s regional rival, Saudi Arabia, and, most importantly, Iran’s arch foe, the United States. These considerations have precluded the emergence of a full-fledged strategic partnership between Iran and Pakistan even after Afghanistan has ceased to be a major source of tensions in the relations of the two countries over the past decade.

Under normal conditions, the United States does not have much to worry about any warm-up in the relations of Pakistan and Iran. But the combination of cold U.S-Pakistan and warm Iran-Pakistan relations can have significant implications for US interests in the region. Given its present military presence in Afghanistan and its continued fight against the Taliban and the remnants of Al-Qaeda, the United States simply cannot afford to simultaneously antagonize Pakistan and Iran. It will either need to engage Iran over Afghanistan and play down other contentious issues in its relations with Iran, or buy Pakistan’s friendship and alliance back.

Given the current level of U.S. hostility and confrontation with Iran, Iran will surely welcome any opportunities to cultivate a coordinated Afghan strategy with Pakistan, should it be sincerely interested in a strategic partnership with Iran. While Iran has welcomed the overthrow of the Taliban regime and has lent its support to the central government in Afghanistan, it would better serve Iran’s security interests if the United States withdraws from Afghanistan and removes its military bases from across the Iranian border in that country. A close partnership with Pakistan at the background of cold U.S.-Pakistan relations will significantly facilitate the realization of that objective for Iran.

Iran will naturally not hesitate to embrace Pakistan in light of its alienation from the United States. The recent statement by Iran’s supreme leader in his meeting with Pakistani president that the United States is the real enemy of Pakistan was meant to further feed into this alienation. Such representation of the United States also resonates well with some segments of the Pakistani political elites and it is also not entirely alien to the Pakistani public in light of the recent developments in U.S.-Pakistan relations and the close U.S.-India partnership in recent years. This explains why some members of the Pakistani parliament recently echoed Khamenei’s statement and branded the United States as “the common enemy of both Iran and Pakistan” and called upon the Pakistani government to abandon its friendship with the United States.

Having said this, it is unlikely that the United States and Pakistan will allow further fallout in their bilateral relations and will most likely strive to patch up their differences. It thus seems more plausible to attach symbolic significance to the recent warm-up in the relations of Pakistan and Iran. Pakistan is genuinely interested in cultivating closer relations with Iran for various reasons, including energy cooperation with Iran, but it seems unlikely that it will seek this relationship at the expense of its relations with the United States.

Given the current confrontational U.S. approach towards Iran and its tendency to picture everything about Iran in a zero-sum game framework, Pakistani leaders may have intended to raise the alarm for the United States by making the impression of seeking closer partnership with Iran. It is plausible that Pakistani leaders may have wished to exert pressure on the U.S. government by sending the signal that any further alienation with the United States would amount to closer Iran-Pakistan relations. This development shows once again how far the U.S confrontational approach towards Iran has created unnecessary costs for its foreign policy and has limited its room for maneuver in the region.