Columnist

Looking at photographs of the ruined, desolate streets of what was once the Islamic State's capital of Raqqa is a reminder of the overwhelming, pitilessly effective military power of the United States.

Perhaps it's a tribute to the inevitable nature of American force, once it's engaged, that the fall of Raqqa in Syria this week provoked so little public discussion. Commentators focused on whether President Trump had dissed the parents of America's fallen warriors, but they barely seemed to notice that our military has achieved a goal that three years ago seemed distant and uncertain.

The heaps of rubble in Raqqa that once housed terrorists and torturers convey a bedrock lesson, as valid now as in 1945: It's a mistake to provoke the United States. It may take the country a while to respond to a threat, but once the machine of U.S. power is engaged, it's relentless — so long as the political will exists to sustain it.

The Raqqa campaign is a reminder, too, of something we rarely see in these divisive days — the continuity of U.S. commitments from the Obama administration to Trump. Truly, it was a shared enterprise. Trump deserves credit for accelerating the campaign against the Islamic State and giving commanders more authority. But the basic strategy — and the will to resist the jihadists in the first place — was President Barack Obama's.

A secure and confident Trump would invite Obama to the White House to meet with commanders and troops returning from the battle. That would remind the world that the United States can keep its word across administrations. Trump, still anxious about his authority, seems incapable of such generosity.

Thinking back to the beginning of this campaign is to recall how fragile it seemed at first. The Islamic State exploded in the summer of 2014, overrunning Mosul and racing like a firestorm across the Sunni regions of Syria and Iraq. The lines of defense buckled. The Kurdish capital of Irbil was in danger; so was Baghdad.

As a condition of U.S. military involvement, Obama demanded a new government in Baghdad that would be less pro-Shiite sectarian and better able to win Sunni trust. He was right, and he got what he wanted in the replacement of Nouri al-Maliki as prime minister with Haider al-Abadi, who has had a steadier hand than Iraq-watchers initially predicted.

When Obama announced his goal to "degrade and ultimately destroy" the Islamic State, it sounded like an obtuse and conditional war aim. And it didn't help that nobody agreed on a name for this enemy, variously called "ISIS," "ISIL" and "Daesh." The United States was hardly enthusiastic for the war after long, frustrating battles against Islamist insurgents in Iraq and Afghanistan. But Obama pushed ahead.

The campaign got off to a slow start. Tribes in Iraq's Euphrates Valley pleaded for U.S. aid that was initially slow to arrive. The Iraqi military was a mess until the U.S.-trained Counter-Terrorism Service began to display real combat power. But gradually, mostly invisibly, the battle turned: U.S. air power killed tens of thousands of recruits to the caliphate, obliterating anyone who raised a digital signal. The U.S. military said little about this harsh campaign, but Syrian and Iraqi fighters saw it, and people go with a winner.

Watching this battle unfold during multiple visits to Iraq and Syria, I saw two factors that changed the tide. First, the United States found committed allies. The toughest fighters initially were Kurdish, the KDP and PUK peshmerga militias in Iraq, and the YPG in Syria. They stood their ground and fought — and died. (This Kurdish loyalty is worth remembering now, in their time of trouble.) The anti-Islamic State alliance broadened as the Iraqi military got stronger, and the YPG recruited Sunnis into an expanded coalition dubbed the Syrian Democratic Forces.

Victory came from marrying these committed fighters to America's devastating firepower. The United States could dial in strikes from an array of platforms — drones, fixed-wing aircraft, advanced artillery. The ruin of Raqqa makes it look like we just pounded everything, and the United States should make a self-critical accounting of civilian loss of life. Honesty about the war's human cost, and U.S. responsibility for mistakes made in the fog of battle, is the best bridge to the future.

The problem with this campaign from the beginning was that our military dominance was patched on top of political quicksand. That's still true. Obama never had a clear political strategy for creating a reformed, post-Islamic State Syria and Iraq; neither does Trump. Our military is supremely effective in its sphere, but the enduring problems of governance, it cannot solve.

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