Predator drones can carry up to two Hellfire missiles. Those have warheads of about 20 pounds, which are designed to pierce tank armor;

Reapers are another story. They feature a maximum payload of 3,000 pounds, or 1.5 tons. That means they can carry a combination of Hellfires and larger 500 pound bombs like the GBU-12 Paveway II and GBD-38 JDAM. Those have an "effective casualty radius" of about 200 feet.

From 2008 through October 2012, there were 1,015 strikes in Afghanistan, 48 in Iraq, and at least 105 in Libya

Primarily al-Qaeda and its affiliates. That includes al-Shaabab in Somalia, al-Qaeda in the Arabian Peninsula (which works in Yemen), and the Haqqani Network in Afghanistan and Pakistan.

Anwar al-Awlaki, an American-born al-Qaeda operative in Yemen, was killed in a drone strike in 2011, as was his American-born 17-year-old son

Ahmed Hijazi, also an American citizen based in Yemen, was killed in 2002. 

The National Counterterrorism Center (NCTC) will prepare lists of potential targets, which will be reviewed every three months by a panel of intelligence analysts and military officials. They are then passed along to a panel at the National Security Council, currently helmed by CIA director nominee Brennan, and then to Obama for final approval.

There is, however, substantial evidence that the percentage of casualties borne by civilians is much lower with drone strikes than with just about any other kind of military intervention

It derives the authority for the strikes from the Authorization for the Use of Military Force (AUMF) passed in the wake of 9/11, which grants the government broad powers against al-Qaeda.

allows states to make war in the interest of self-defense

Critics, like UN special rapporteur on extrajudicial killings, summary or arbitrary executions Christof Heyns, say that this defense is a stretch, and the killings plainly run afoul of the laws of war and international human rights treaties.

Only the United States and the United Kingdom (which assists in the Pakistan drone effort) currently use drones in combat

All told, the GAO estimates that 76 countries, at least, have drone technology.

The Yemeni government quietly agreed to the strikes

Citizens in both countries deplore the campaigns.

there are deeper doubts as to whether the strategy is recruiting more militants than it kills, by turning local populations against the United States.

Critics of drone strikes often fail to take into account the fact that the alternatives are either too risky or unrealistic.

Even the most unfavorable estimates of drone casualties reveal that the ratio of civilian to militant deaths is lower than it would be for other forms of strikes.

signature strikes,” which target not specific individuals but instead groups engaged in suspicious activities.

After a strike in Pakistan, militants often cordon off the area, remove their dead, and admit only local reporters sympathetic to their cause or decide on a body count themselves. The U.S. media often then draw on such faulty reporting to give the illusion of having used multiple sources. As a result, statistics on civilians killed by drones are often inflated.

data show that drones are more discriminate than other types of force.

Yemen’s former president, Ali Abdullah Saleh, also at times allowed drone strikes in his country and even covered for them by telling the public that they were conducted by the Yemeni air force.

As officials in both Pakistan and Yemen realize, U.S. drone strikes help their governments by targeting common enemies.

A 2012 poll found that 74 percent of Pakistanis viewed the United States as their enemy, likely in part because of the ongoing drone campaign. Similarly, in Yemen, as the scholar Gregory Johnsen has pointed out, drone strikes can win the enmity of entire tribes.

Many surveys of public opinion related to drones are conducted by anti-drone organizations, which results in biased samples.

And for most Pakistanis and Yemenis, the most important problems they struggle with are corruption, weak representative institutions, and poor economic growth; the drone program is only a small part of their overall anger, most of which is directed toward their own governments.

The US has launched four drone strike in Yemen since the beginning of 2015.

The US lost its biggest partner in Yemen when the Houthis took control of Sana’a and forced President Abd Rabbo Mansour Hadi and the government to resign.

US officials have insisted that counterterrorism operations against AQAP will continue.

President Obama previously praised the US counterterrorism strategy in Yemen as “one that we have successfully pursued.”

The Houthis, though bitter enemies of Al Qaeda, have publicly opposed American drone strikes in Yemen. But they have apparently done nothing to interfere with the strikes since they took de facto control last month, and the American military has said the strikes will continue.

Mr. Nadhari praised their actions and said that France would face further attacks if it did not halt its “aggression against the Muslims.”

In 2011 an unmanned combat drone killed his father and teenage brother as they were out herding the family’s camels.

the Tuaiman men have been involved in pushing back against the Houthis.

Maqdad said the family had been wrongly associated with al-Qaida, and family members strongly deny that Mohammed was involved in any al-Qaida or anti-Houthi fighting.

evacuation of the US embassies

The battle between Al Qaeda, the Houthis, and Yemeni nationals to secure control of the country has left it on the brink of a civil war,