When he visits Pakistan this week, Secretary of State Rex Tillerson will find his hosts anxious about what the Trump administration has in mind for them. Despite the dramatic rescue of an American woman and her family by Pakistani troops earlier this month, relations between Washington and Islamabad are in turmoil.

It is not clear that Tillerson understands the depth of Pakistani uneasiness about its putative counterterrorism partner. Nor is it apparent that he has a strategy for putting the relationship on a more solid basis. Above all, the Pakistanis are unsettled about Trump’s new policy toward Afghanistan, unveiled in an Aug. 21 speech.

Explaining his new approach, Trump bluntly accused Pakistan of sheltering terrorist groups “that try every single day to kill our people.” That will have to change, Trump warned, “and that will change immediately.” Vice President Mike Pence declared that Trump had put Pakistan “on notice.”

One day after the Trump speech, Tillerson was asked what leverage Washington possessed to persuade the Pakistanis to behave better. “Obviously, we have some leverage…in terms of the amount of aid and military assistance we give them, their status as a [major] alliance partner. All of that can be put on the table.”

Many Americans applauded this seemingly tougher approach to Pakistan. But those familiar with the history of the bilateral relationship had a sinking feeling of déjà vu, as we have been down this road before, with decidedly mixed results. Trump believes in American power and in the leverage that it offers. This is not an unreasonable position. Indeed, despite the obvious challenges it confronts, the United States remains the world’s strongest nation, by a considerable margin.

But translating American power into diplomatic leverage is not always as easy as many assume. If it were, we would not be continually frustrated by the likes of North Korea, Iran, Cuba, and even Russia. A close look at relations between the United States and Pakistan over the decades offers a number of guidelines about how best to turn U.S. power into leverage.

First, we should not overestimate the value of U.S. favor or the attraction of U.S. carrots. Throughout the 1980s, the Reagan administration regularly warned Islamabad that unless it capped its nuclear program, U.S. law would require a termination of all assistance. That threat of course turned out to be wholly ineffectual in halting the Pakistani program.

More recently, Congress and the Obama administration tripled U.S. economic aid to Pakistan, in the hope that this concrete demonstration of American friendship would ease Pakistani security anxieties and nudge Islamabad toward policies more to Washington’s liking. As Trump’s Aug. 21 speech indicates, that didn’t prove sufficient to wean Pakistan from its covert partnership with extremist groups like the Haqqani network.

Second, leverage is not likely to work if Pakistan believes it is being asked to sacrifice core interests. From the American perspective, Pakistan has never been “all in” in the war on terrorism. Since 9/11, Islamabad has valued the U.S. connection as a way to ensure that Afghanistan would be governed by a friendly regime, with little or, better yet, no Indian influence.

"Ignoring this Pakistani bottom line is guaranteed to negate whatever leverage capabilities U.S. power might otherwise possess."

By inviting New Delhi to play a larger role in Afghanistan, the new Trump policy, instead of soothing Islamabad’s fears about an Indian presence in Afghanistan, has inflamed Pakistani anxieties. Ignoring this Pakistani bottom line is guaranteed to negate whatever leverage capabilities U.S. power might otherwise possess.

Third, to be successful, a country attempting leverage must minimize its dependence upon the target country. This reality has hampered U.S. diplomacy from the very beginning of the war in Afghanistan. Because it shares a long border with Afghanistan, Pakistan’s cooperation has been vital to the U.S. war effort. Supplying American and NATO troops in Afghanistan has depended on Pakistani ground and air routes.

Despite the serious limitations of the partnership, Pakistan has provided the United States with valuable intelligence and logistical support, the use of Pakistani military bases, acquiescence in repeated violations of Pakistani territory by drones and Special Forces operators, and at least periodic arrests of Taliban and Al Qaeda fighters. Islamabad’s ability to satisfy important American needs has given it the ability to deflect or ignore U.S. wishes, even those about which Washington felt strongly. That remains the case today.

Fourth, diplomatic tone and style can either enhance or undercut leverage. Threats, bluster, and public ultimatums make good political theater at home, but probably not good leverage. Less powerful countries in particular are sensitive to slights, actual or perceived, and alive to the danger of being “humiliated.”

Threatening a weaker country, especially in public, often produces the exact opposite response from that intended. This expectation that they be treated with dignity helps explain why Pakistanis so strongly resent congressionally imposed conditions on U.S. aid. Rather than a symbol of American friendship, aid is seen as evidence of U.S. manipulation and dark designs.

"Putting the squeeze on Pakistan to get it to be a better counterterrorism partner may make sense. But squeezing can also backfire."

Putting the squeeze on Pakistan to get it to be a better counterterrorism partner may make sense. But squeezing can also backfire. Before Tillerson proceeds along this path, he ought to have a clear understanding of the reasons behind America’s very indifferent record in trying to exert leverage on Pakistan.

This article was originally published in The Hill. 

The opinions expressed here are solely those of the author.