Some of us are saying goodbye to our servicemembers -- headed out on another long wartime deployment -- for the third and fourth time. Some of us are saying, "See you in six months ...15 months ..." and even more.

Why are the people we love gone so much? The answer to that may seem obvious -- there's a war on, of course. But why are we using the military to solve so many of our problems? Why does it seem like we and our servicemembers are the only ones making real sacrifices to protect our national interests?

While researching my cover story for the Washington Post Magazine, "Us and Them: Their War," I discovered that it's partly because few Americans today understand what the military can and cannot do. This is even true for many of our national leaders. But they also don't know much about diplomacy either. Analysts are sounding the alarm that over the past 30 years, Congress and a succession of presidents have neglected the State Department. They've relied too much on the military, saddling it with nation-building tasks.

"The tools for creating and building have withered away, even though we have recognized that they are important to the security fight," observes Sarah Sewall, a former deputy assistant secretary of defense now at Harvard's Kennedy School of Government. "It brings to mind the old saw -- if the only tool you have is a hammer, every problem looks like a nail."

The State Department doesn't just suffer from limited budgets and limited numbers of people. It also has no way to get its people where they need to be on short notice, and can't force them to go if they don't want to. Only the military has the power to order people to go. Only the military has ships and planes to move large numbers of those people to remote areas around the world and the logistics systems to keep them equipped and fed once they get there.

Retired Marine Gen. Anthony Zinni has proposed a deployable State Department force of economists, judges and other nation-building experts in his book, The Battle for Peace. Like military reservists, they would hold regular civilian jobs but could be called up and deployed as needed.

"It's not just a lack of capability, though," cautions Sewall. "What we have are leaders who fail to appreciate how those capabilities might be used, civilians who don't understand the uses, limits and security impact of non-military tools."

We military family members often know more about military-related issues than our civilian leaders just because we're exposed to it through our service members. My husband's service certainly got me thinking in ways I never did before he joined.

Personal military experience used to teach many civilians the way it taught Chuck Hagel, Nebraska's Republican senator. In Vietnam, he survived ambush patrols in the jungle and house-to-house fighting during the Tet Offensive. Nowadays, Hagel is one of only a handful of combat veterans in the Senate.

Combat changes people. Peter Feaver and Richard Kohn, editors of Soldiers and Civilians: The Civil-Military Gap and American National Security, conclude from their research, "At least as far back as 1816, the more veterans there are in the national political elite, the less likely the United States is to initiate the use of force in the international arena." Apparently, fighting one war tends to make you wary about fighting another one.

Hagel, a businessman as well as a veteran, argues, "Economic and diplomatic power are part of those instruments of power that a great nation has, as well as its military power."

He tells the story of an Air Force colonel's wife who stood up at a breakfast meeting in Nebraska and pointed out that America is asking a very small percentage of people to carry all the burden and make all the sacrifices, while the rest of the country gets tax cuts.

Less than 1 percent of the population serves in the military these days. The result? While nearly two-thirds of military leaders believe they share the same values as the American people, only about one-third of their civilian counter-parts agree, according to surveys by the Triangle Institute for Security Studies, an academic think tank in North Carolina.

"We are disconnecting from our society," Hagel says about the military. "The consequences are: One, you commit military wherever you think you need them, kind of like committing foodstuffs or some commodity. We'll send a carload of grain to the Sudan. We'll send -- I hear a lot of this -- let's send two more brigades into Iraq. Well, you stop and ask the question: Do you realize what you're saying?"

He points at the air, at the unseen consequences. "You're saying, of course, there will be a number of casualties, and the suffering, and the separation from the families, and the sacrifices. If you have a congressman who's experienced this, you would see the Congress be far more careful and more cautious, if for no other reason than they know what this is about."

Hagel sits back. "Second, I don't think you want a free society where you've got a very clear difference between the people and the paid professional military... and whatever trouble we get into we'll just send them over."

And how does that hurt anybody besides the military?

"It disconnects the people from the kind of commitment and sacrifice that goes into this," Hagel says. "You then raise another generation of Americans thinking they have no obligations." He concludes, "That's the real danger here. Service. Citizenship. What is the responsibility of a citizen?"