University of Texas historian Jeremi Suri takes a historical approach to this question. Here is a taste of his piece at The New York Times;
History is clear: We would be better off with more modest, restrained military and strategic goals. U.S. public opinion seems to have moved in this direction, too. Our country needs to re-examine the value of military dominance.
The reliance on military force has repeatedly entangled the United States in distant, costly, long conflicts with self-defeating consequences — in Vietnam, Lebanon, Iraq, Afghanistan and other places. American leaders have consistently assumed that military superiority will compensate for diplomatic and political limitations. Time and again, despite battlefield successes, our military has come up short in achieving stated goals.
In the Korean War, the overestimation of American military power convinced President Harry Truman to authorize the Army to cross into North Korea and approach the border of China. He hoped American soldiers could reunite the divided Korean Peninsula, but instead the incursion set off a wider war with China and a stalemated conflict. Now, after seven decades of American military deployments on the peninsula, the Communist regime in North Korea is as strong as ever, with a growing nuclear arsenal.
In Vietnam, the “best and brightest” experts around President Lyndon Johnson advised him that America’s overwhelming power would crush the insurgency and bolster anti-Communist defenses. The opposite was true. American military escalation increased the popularity of the insurgency while also creating greater South Vietnamese dependence on the United States. Following an offensive by North Vietnam in 1975, American-trained allies collapsed, much as they did in Afghanistan this summer.
The fault lies not with the soldiers, but with the mission. Military forces are not a substitute for the hard work of building representative and effective institutions of governance. Stable societies need to have a foundation of peaceful forms of trade, education and citizen participation.
If anything, the record shows that a large military presence distorts political development, directing it toward combat and policing, not social development. American military occupations have worked best where the governing institutions preceded the arrival of foreign soldiers, as in Germany and Japan after World War II.
Read the entire piece here.