I don’t agree with Andy Bacevich’s fundamental take on the Iraq war, but this passage in his Washington Post op-ed serves as a useful reminder that military force is a very blunt instrument:

Whereas technology was supposed to render the battlefield transparent, the “fog of war” settled over Iraq like a suffocating blanket. Never have U.S. forces fought in such ignorance of the enemy’s purpose, strength, leadership and order of battle. George Armstrong Custer knew more about the warriors he faced in 1876 than U.S. commanders today know about their adversaries.
Whereas precision weapons were supposedly making error, waste and collateral damage a thing of the past, the fight to control Iraqi cities has given the past a new life. Comparisons between the “liberation” of Fallujah and the Marines’ assault on Hue in 1968 are only too apt. In both cases, victory was gained the old-fashioned way: through brute force.
Toppling Saddam Hussein opened a Pandora’s box of unanticipated complications. Whether it was attacks on oil pipelines or insurgents infiltrating into the new Iraqi security forces, events time and again caught U.S. officials flat-footed. Even success proves transitory, with yesterday’s apparent accomplishment becoming unglued today.
To which anyone with even a passing knowledge of history would reply: of course. This is what war has always been — grueling, filthy, confusing, replete with accidents and miscues that victimize the innocent, giving rise to unforeseen consequences and loose ends.