What do you call an ally that tries to kill you? That's the question most Americans are asking in the wake of last month's dissemination by Internet clearinghouse WikiLeaks of some 92,000 classified U.S. military documents relating to the war in Afghanistan. The files provide a sobering portrait of the true state of play on the War on Terror's first front. Far and away the most damaging disclosures, however, are those relating to the pernicious role being played by Pakistan, long regarded as a critical American ally in South Asia, in supporting and sustaining the anti-Western insurgency there.

"The documents clearly show that the Pakistani intelligence agency is the most important accomplice the Taliban has outside of Afghanistan," Germany's influential Der Spiegel, one of the few news outlets with direct access to the WikiLeaks files, reports. "The war against the Afghan security forces, the Americans and their ISAF allies is still being conducted from Pakistan." Specifically, the news magazine reports that, "according to the war logs, the ISI envoys are present when insurgent commanders hold war councils--and even give specific orders to carry out murders."

Truth be told, this duplicitous role has been an open secret for some time. The Taliban, after all, is a product of Pakistan's feared Inter Services Intelligence (ISI), which fostered the puritanical Islamist movement in the early 1990s as a way of projecting power into neighboring Afghanistan. And once the Taliban succeeded in seizing power there in 1996, the ISI provided it with the financial and political backing to retain and strengthen its control. But all that was supposed to have ended after 9/11, when Islamabad grudgingly bought into the Bush administration's offensive against al Qaeda and the Taliban (albeit after some serious arm-twisting by then-Deputy Secretary of State Richard Armitage).

Yet the U.S.-Pakistani partnership has been troubled from the start. Anti-Americanism is rife in Pakistan; in the most recent Pew Global Attitudes survey of Pakistani public opinion, just 17% of respondents had a positive view of the U.S. And the country's conspiracy-prone population has tended to treat the U.S.-led Coalition, rather than its own internal Islamist plague, as the source of all its ills.

The Bush administration glossed over this unsettling state of affairs. Islamabad, under the leadership of Pervez Musharraf (and subsequently Asif Ali Zardari), was touted as a major ally in the War on Terror and a key player in securing post-Taliban Afghanistan, despite irrefutable proof that Pakistan was effectively playing both sides of the political fence.

Under Obama, the situation has gotten even more muddled. Early on in its tenure, the new White House outlined a comprehensive new strategy for Afghanistan and Pakistan, colloquially known as "AfPak," that explicitly linked stability in Afghanistan with the pace of reform across the border in Pakistan. But this clarity of vision turned out to be short-lived. By last fall, the White House had stepped back from any sort of explicit linkage between Afghanistan's unrest and Pakistani influence, instead focusing simply on the need "to disrupt, dismantle and defeat al Qaeda in Afghanistan and Pakistan, and to prevent its capacity to threaten America and our allies in the future."

All of which begs the question: Why does Washington continue to treat Islamabad with kid gloves?

The reasons are essentially two-fold. First, there's Islamabad's burgeoning nuclear arsenal. Pakistan, home base to all manner of Islamic radicals, is also one of South Asia's strategic heavyweights. Ever since 1998, when India and Pakistan carried out a series of tit-for-tat nuclear tests, South Asia has been the site of an uneasy bilateral geopolitical balance. And while one side of the equation, India, is stable, prosperous and democratic, the other is decidedly not. Plagued with a rising tide of Islamic radicalism and notoriously weak central institutions, Pakistan is perilously close to becoming a nuclear rogue state. That frightening possibility has left Washington with little choice but to bank on the powers that be in Islamabad, seeking to preserve rather than reform them.

Second, and related, is Pakistan's role in combating al Qaeda and the Taliban on its own territory. In recent years Pakistan's troubled border regions, the Federally Administered Tribal Areas (or FATAs) and North West Frontier Province (NWFP), became breeding grounds for Islamic radicalism as Islamabad was slowly but surely shouldered out of power there. Under Musharraf, the Pakistani government responded weakly, proffering a truce to regional militants in exchange for a measure of stability in its hinterlands. The deal did not hold, however. Emboldened by what they saw as governmental weakness, Islamic radicals spilled out of Pakistan's border regions to threaten the stability of the country's interior.

All of which has led to something of an ideological about face in Islamabad. In recent weeks the Pakistani government has stepped up its activities against at least certain elements of the Taliban--those operating on its own territory and against its interests. But the WikiLeaks documents underscore that Pakistan's transition from terror sponsor to counterterrorism partner is still tenuous at best.

At worst, it is simply a tactical feint designed to deflect international criticism--and to keep American aid flowing. And flowing it is. Last year Congress approved a mammoth $7.5 billion foreign aid package for Pakistan--one that places only nominal oversight, and virtually no limitations, on Pakistan's use of American taxpayer dollars.

So, can American treasure succeed where American blood has failed, and help Islamabad take a more sympathetic turn? Perhaps. But these days, it's hard to argue with the notion that our partnership with Pakistan has become much more of a liability than an asset, in both economic and human terms.

Ilan Berman is vice president of the American Foreign Policy Council in Washington, D.C. His column, Present Dangers, appears monthly.