Americans observe the most recent political maneuvering in Pakistan—a withdrawal from the governing coalition by the Muttahida Qaumi Movement (MQM), depriving the government of Prime Minister Yusuf Raza Gilani of a parliamentary majority—with perpetual nervousness about this South Asian nation of more than 170 million. The nervousness has intensified over the past couple of years. Clearly the multiple roles that Pakistan is playing in the conflict in Afghanistan are mostly responsible for this. Americans on different sides of the Afghanistan war issue agree that there is a problem of Afghan insurgents finding sanctuary on the Pakistani side of the Durand Line, and that there is a further problem of Pakistani officialdom retaining old ties with the Afghan Taliban.

Then there are Pakistan's nuclear weapons, which are frequently invoked as an even graver source of worry. In fact, the presumed causal relationships in the Af/Pak theater often get flipped around by people who at least tacitly acknowledge that the counterinsurgency in Afghanistan isn't really doing much to put al-Qaeda out of business. Pakistan is the real prize, so it is said; the most important reason we are supposedly in Afghanistan is to prevent instability from spreading across the border and causing Pakistan to shake apart. The specter haunting such discussions is one of mad mullahs getting their hands on those nuclear weapons.

There's no doubt that Pakistan represents a heap of headaches for the United States these days. There is indeed a lot about which to worry. I would put at the top of the list of worries the underlying volatility of the relationship between Pakistan and India, and the fact that South Asia is still the region with the greatest chance of a nuclear war breaking out. And there is no doubt that Pakistan presents major problems for what NATO is trying to accomplish in Afghanistan, and is likely to continue to do so. Pakistan simply does not see its interests as running in the same direction in Afghanistan as the way that the United States and NATO have defined their objectives there. As for mad mullahs and the nukes, however, I don't see a cause for so much worry. The specter is just that; it is not a scenario. I have yet to hear a plausible path that would bring Pakistan to that nightmare.

The current politicking in Islamabad also should not be worrisome. It looks a lot like vibrant politics in representative democracies that are much more firmly established democracies than is Pakistan. The MQM is just playing good old parliamentary hard ball. Its declared reason for withdrawing from the governing coalition has to do with subsidies and consumer prices, but it may also be using these issues as leverage to win concessions on some questions having to do with local governance in its stronghold of Karachi.

In many countries this kind of political instability would be discouraging to foreign interlocutors, because of the uncertainty about who will be in charge next month or next year and whether the same policy direction will continue. But here is where the gross imperfection of Pakistan's democracy helps. On the issues and policies that matter most to the United States, the Pakistani military—and in particular the chief of the army staff, General Ashfaq Kayani—makes the decisions. This is certainly true of everything having to do with military operations against militants in the northwest, as well as the military posture vis–à–vis India.

In the six decades since independence, Pakistan has alternated between civilian and direct military rule. Whenever the Pakistani people get sufficiently fed up with one of those two arrangements, it makes enough of a fuss that everyone knows it's time for a change. This pattern probably will continue. The civilians have been back only for a couple of years so far, so it probably will be a few more years before the next military takeover. But through this all, the Pakistani military has been the principal power behind the scenes if it has not been at the front of the scene. It is the most cohesive Pakistani institution and the strongest one, and not just in the sense that it has the guns. It also is, despite all the political involvement, a professional military force. All of these qualities are among the chief reasons it is extremely unlikely the religious extremists who are getting the attention in the northwest will ever get their hands on the nukes.

Now, if the United States really wanted to do something to foster stability in Pakistan, it could respond positively to Pakistan's old request to let its important textile industry market more of its product in the United States. But that doesn't seem to be happening. Evidently for some economic interests there are some things, such as foreign competition, that are even scarier than mullahs with nuclear weapons.