A snippet from Robert Gates's speech a few days ago:

First, limits about what the United States - still the strongest and greatest nation on earth - can do. The power of our military's global reach has been an indispensable contributor to world peace - and must remain so. But not every outrage, every act of aggression, every crisis can or should elicit an American military response, and we should acknowledge such.

Be modest about what military force can accomplish, and what technology can accomplish. The advances in precision, sensor, information and satellite technology have led to extraordinary gains in what the U.S. military can do. The Taliban dispatched within three months, Saddam's regime toppled in three weeks. Where a button is pushed in Nevada and seconds later a pickup truck explodes in Mosul. Where a bomb destroys the targeted house on the right, leaving intact the one on the left.

But also never neglect the psychological, cultural, political, and human dimensions of warfare, which is inevitably tragic, inefficient, and uncertain. Be skeptical of systems analysis, computer models, game theories, or doctrines that suggest otherwise. Look askance at idealized, triumphalist, or ethnocentric notions of future conflict that aspire to upend the immutable principles of war: where the enemy is killed, but our troops and innocent civilians are spared. Where adversaries can be cowed, shocked, or awed into submission, instead of being tracked down, hilltop by hilltop, house by house, block by bloody block.

Thomas P.M. Barnett has the rest of the speech and his own analysis.

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