NEW YORK — The first time I met Gen. David Petraeus, he said something that surprised me. It was the early days of the Iraq War and, while things were not going well, he had directed his region in the north skillfully and effectively. I asked him whether he wished he had more troops. Petraeus was too politically savvy to criticize the Donald Rumsfeld “light footprint” strategy, so he deflected the question, answering it a different way. “I wish we had more Foreign Service officers, aid professionals and other kinds of non-military specialists,” he said. The heart of the problem America was facing in Iraq, he noted presciently, was a deep sectarian divide between Shiite and Sunni, Arab and Kurd. “We need help on those issues. Otherwise, we’re relying on 22-year-old sergeants to handle them. Now, they are great kids but they really don’t know the history, the language, the politics.”

I thought of that exchange when reading reports that President Trump is expected to propose a $54 billion increase for the Defense Department, which would be offset by large cuts in the State Department, foreign aid and other civilian agencies. Trump says he wants to do this so that “nobody will dare question our military might again.” But no one does. The U.S. military remains in a league of its own. America’s defense budget in 2015 was nine times the size of Russia’s and three times that of China’s.

None of the difficulties the United States has faced over the past 25 years has been in any way because its military was too small or weak. As then-Defense Secretary Robert Gates noted in a 2007 lecture, “One of the most important lessons of the wars in Iraq and Afghanistan is that military success is not sufficient to win.” At that time and on several other occasions he argued that “there is a need for a dramatic increase in spending on the civilian instruments of national security — diplomacy, strategic communications, foreign assistance, civic action and economic reconstruction and development.”

No smart adversary will try to take on the U.S. military tank for tank or ship for ship. It will fight with asymmetrical tactics like local insurgencies, terrorism and cyberwar. And combating any of these challenges will require better non-military capacity. Consider the strategy that brought Iran to the negotiating table in 2013. It required intense diplomatic work to get Russia and China to agree to U.N. sanctions and to isolate Iran from neighbors like Turkey. It took clever and tough sanctions devised by the Treasury Department that leveraged America’s financial power. This is how power works in the modern world.

“We must do a lot more with less,” said Trump recently, explaining that government needs to reform its ways. But the obvious target for this effort should be the Pentagon, which is the poster child for waste in government. The Pentagon is now the world’s largest bureaucracy, running a cradle to grave quasi-socialist system of employment, housing, health care and pensions for its 3 million employees. A recent report from its own Defense Business Board concluded that it could easily save $125 billion over five years by removing operational inefficiencies. (Senior officials quickly buried the report and it has gone nowhere.) Those cost savings would fund the entire State Department plus all foreign aid programs two and half times over. Gates used to quip, “We have more people in military bands than we have Foreign Service officers.” The total numbers are worth noting. There are only 13,000 employees in the whole foreign service, compared with 742,000 civilians in the Department of Defense.

Trump railed in his address to Congress, as he has in the past, about the $6 trillion that the United States has spent in the Middle East. That figure is exaggerated, but he’s right that when the Pentagon goes to war, costs go through the stratosphere. In just one example, ProPublica tallied up the audits of the special inspector general for Afghanistan and found that the military had wasted at least $17 billion on a variety of projects.

Rosa Brooks, who served as a civilian adviser at the Pentagon under President Obama, has written a fascinating book, “How Everything Became War and the Military Became Everything,” that describes how American policy has been contorted by a military that keeps expanding while all other agencies wither. One of the blurbs on the back of the book says, “One of the most thought-provoking books I’ve ever read. It’s as if we have been sleepwalking into this new world and Rosa has turned on a flashlight.” The commendation comes from James Mattis, now the secretary of defense. Perhaps he should give the book to his boss.

Fareed Zakaria is a columnist with The Washington Post. His email address is: comments@fareedzakaria.com.

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