Between April 19 and 21, the US launched a series of airstrikes in Yemen that killed somewhere between 39 and 70 militants and between three and 10 civilians. The campaign, coordinated with Yemeni ground forces, was arguably the most serious US military escalation in Yemen up until that point — a sign of how concerned Washington was by the threat from al-Qaeda in the Arabian Peninsula (AQAP).
Why did the US bomb Yemen in April 2014?
Between April 19 and 21, the United States launched a bombing campaign in Yemen. The strikes apparently had "been planned for quite some time," according to US officials, and were directed at Yemen's powerful al-Qaeda affiliate, al-Qaeda in the Arabian Peninsula (AQAP). The campaign killed somewhere between 37 and 70 militants, as well as three to 10 civilians, depending on whose tally you believe.
This is particularly unusual given that the United States had been dialing down its use of drones against suspected terrorists around that time in both Yemen and Pakistan. The April 2014 campaign suggested the US still saw airstrikes as an effective means for countering al-Qaeda in Yemen.
Yemen is the Arab region's poorest country by GDP per capita, located at the southern tip of the Gulf peninsula. The country's weak government had been wracked by civil wars for decades — even before the government's total collapse in late 2014 and early 2015. The long-term chaos has been practically a welcome mat for AQAP, which is now arguably the strongest al-Qaeda affiliate in the world.
The US government has linked AQAP to several attempts to attack the United States, including Umar Farouk Abdulmutallab's abortive 2009 attempt to stuff bombs in his underwear and board a plane. The argument for the 2014 campaign was that, left alone, AQAP will attempt to hit the United States again — and eventually, it will succeed.
The case against the strikes was equally simple: drone strikes haven't destroyed AQAP so far, but they have killed a lot of civilians.
Hadn't the US been bombing Yemen before April 2014?
The first American attack on suspected terrorists was in 2002, but the bombing campaign in Yemen didn't really pick up speed until 2011. Both the total number of strikes and the casualties from them peaked in 2012, as you can see in the below chart.
Attacks peaked in 2012 because Yemen was, from an American point of view, at a particularly dangerous point. Al-Qaeda had seized control of several cities in the south of Yemen, and the country's pro-American dictator, Ali Abdullah Saleh, had just been overthrown by Arab Spring–related unrest. The goal of American strikes was to degrade al-Qaeda's ability to take advantage of Yemen's instability and, ultimately, to beat it back.
Yemen's new President at the time, Abd Rabbu Mansour Hadi, publicly endorsed drone strikes against al-Qaeda in September 2012. He had built a close security relationship with the US, and the April 2014 bombing campaign was best seen as a joint American-Yemeni operation. Yemen provided the ground troops and some intel, and the US provided the airpower.
Why did the US launch such an intense campaign in April 2014?
America's basic goals in the April campaign were the same as they've always been: limit al-Qaeda's ability to strike American targets and shore up the Yemeni government's advantage over al-Qaeda. The offensive has hit large groups of al-Qaeda fighters, but there was speculation that the US also targeted, but failed to hit, al-Qaeda's top two leaders in Yemen.
During the operation, US planes and Yemeni troops conducted a combined operation against al-Qaeda strongholds in the south of Yemen, the group's strongest region. It was coordinated to the point where American helicopters dropped Yemeni special forces into targeted zones to confirm the identity of those killed.
The offensive concentrated on two targets: a group of international al-Qaeda fighters that recently arrived from Syria and a Yemeni training camp.
It's unclear yet whether the real goal, as many have speculated, was to kill the top leaders of al-Qaeda in the Arabian Peninsula (AQAP). Just before the strikes, AQAP's leader, Nasir al-Wuhayshi, released a video "renewing" his pledge to hit the United States. And the US has long been after Ibrahim al-Asiri, an AQAP bombmaker with a proven capability to build explosives that circumvent Western detection.
The fact that the US dropped Yemeni soldiers into the strikes to identify the dead certainly suggests the point may have been to get Wuhayshi or Asiri. But as Gregory Johnsen and Miriam Berger note, there's no actual confirmation of that.
Did the US bombing campaign in Yemen hurt al-Qaeda?
It's possible, but even with the benefit of hindsight it's hard to know for sure.
There's some real evidence that strikes like the ones in Yemen have damaged organizations such as al-Qaeda in the past. Political scientists Patrick Johnston and Anoop Sarbahi put together data suggesting that in Pakistan, Taliban and al-Qaeda attacks declined when US bombing campaigns intensified. The basic logic is that if you target open organization like training camps, as the US just did in Yemen, then the groups are far less capable of attacking US or Yemeni targets.
At least one piece of ground-level evidence backs up that theory. In 2012, University of Virginia fellow Christopher Swift traveled to Yemen and interviewed Yemeni tribal leaders and politicians about the drone strikes.
Swift's interviews suggested the common theory that drone strikes were helping al-Qaeda was mistaken. Yemenis were joining al-Qaeda for economic reasons, not out of anger at the US. And the strikes were successfully killing al-Qaeda fighters, which appears to be what just happened.
However, even this evidence is sketchy. A recent review of the statistical research on targeted killing campaigns, funded by the US government's Strategic Studies Institute, found no conclusive evidence one way or another that strikes hurt the Taliban in Afghanistan. Different statistical studies came to different conclusions, and the data just isn't good enough to distinguish between them.
Without any more direct evidence, then, it's really hard to say whether this campaign, or subsequent ones like it, did real harm to AQAP.
Did the US bombing campaign in Yemen kill civilians?
The US campaign planners knew in advance that the risk of civilian casualties was high. Between 2009 and April 2014, somewhere in the range of 10 and 20 percent of all people killed by US drone strikes in Yemen were civilians, depending on the source. In December 2013, a US strike hit a Yemeni wedding party by mistake, killing 12.