Pakistan will soon have the fifth-largest population in the world. It already has the seventh-largest army and is close to overtaking Britain as the fifth-largest nuclear power. The country’s location, demographic heft, military might, nuclear weapons capability and links to Islamist terrorists ensure that it will remain central to U.S. interests even after NATO forces depart Afghanistan.

In other words, as much as some might like it to be otherwise, writing Pakistan out of the U.S. foreign policy script is not an option. This is true even in the aftermath of last weekend’s NATO airstrikes that killed 24 Pakistani soldiers, triggering yet another crisis in the tortured U.S.-Pakistan relationship.

Two years ago, when one of us served in Congress, there was robust debate over the nature of the U.S. relationship with Pakistan — the need for more civilian control, especially over the nuclear arsenal, and Islamabad’s failure to crack down on corruption and domestic extremists. The debate culminated in President Obama signing the Kerry-Lugar-Berman (KLB) Act, committing the United States to provide $1.5 billion in annual economic assistance for the next five years.

Fierce opposition from the supercharged Pakistani media over questions of sovereignty threatened to derail the bill, which sought to reorient a predominantly military relationship into a long-term civilian-based partnership. In passing KLB, Congress wagered that, by investing in Pakistan’s political and economic development, the United States could play a small but meaningful role in creating a prosperous, tolerant and inclusive nation that would be a force for peace and stability throughout South Asia.

Today, the United States still struggles to fashion an effective program of civilian aid. Many Pakistanis claim they see no evidence of U.S. economic assistance. Others contend that the U.S. Embassy in Islamabad has poorly managed the program, imposing “Made in America” solutions on Pakistani problems. Some question whether KLB reflects Pakistani priorities or an U.S. agenda that may be harmful to Pakistani interests.

Similarly, in this country and specifically on Capitol Hill, many are reevaluating their support. The revelation that Osama bin Laden had been hiding in plain sight in Pakistan led some to reassess the assumption that the countries share a common counterterrorism agenda. Others rightly resent Pakistan’s unwillingness to undertake tough economic reforms as a step toward helping itself. Still others wonder why we should assist a country where virulent anti-Americanism is pervasive.

The case of those who argue that our first responsibilities lie at home has been strengthened by a profusion of domestic needs, including economic distress and a stubborn jobless rate. To a Congress frantically looking for ways to slash spending, economic assistance to Pakistan will be an easy target — but an utterly wrongheaded move.

Reflecting the widespread concern in both countries that KLB was in trouble, the Woodrow Wilson Center organized a 17-member working group this year to evaluate the program and determine whether circumstances since passage of the KLB bill warranted reducing U.S. assistance.

The report, released this week, concludes that a robust program of U.S. civilian assistance to Pakistan serves important U.S. interests but warns that substantial mid-course corrections are needed if KLB is to fulfill its proponents’ hopes. Congress should not confuse security aid to the Pakistani military with economic assistance designed to shore up civilian political capacity; food, health and energy shortfalls in Pakistan must be addressed; and the groundwork must be laid for a successful Pakistan and a long-term U.S.-Pakistani partnership.

U.S. assistance is not a Pakistani entitlement; and Pakistan, which has one of the lowest tax rates in the world, should do much more to generate revenue. American aid should augment, not replace, Pakistani funding. To this end, we should require Pakistani investment in most KLB aid projects, which will ensure that our priorities are aligned. We should accelerate our efforts to help build Pakistan’s small-business sector, which will provide most new jobs, and must resist the temptation to believe that trade can replace aid; both are crucial for Pakistan’s development.

We must also enhance the U.S. government’s ability to deliver aid quickly and effectively by recruiting more seasoned technical experts, extending the Pakistan tours of U.S. aid officials and bringing local civil-society organizations and prospective beneficiaries more fully into the design, implementation and evaluation of aid projects.

We should insist that Pakistan’s government do more to curb corruption and strengthen political capacity. And we should live up to our pledge to provide Pakistan with $1.5 billion a year in economic assistance through 2014. Without it, things will only get worse and more dangerous for America.

If we are mad at Pakistani failures in the security realm, we should not take our frustrations out on the Pakistani people, who are the primary beneficiaries of KLB and who have absolutely no control over the army.

Jane Harman, a former Democratic representative from California, is president of the Woodrow Wilson International Center for Scholars. Robert M. Hathaway directs the center’s Asia program.