In 2008 Barack Obama campaigned to end Bush-era policies that, he said, created a false choice between our safety and our ideals. Now that the war in Iraq is over and the war in Afghanistan is winding down, there is no indication the liberal constitutional-law professor will become a peacenik president—or even pull back on some of his more aggressive counterterrorism measures.

For the first time in more than 40 years, Democrats hold the advantage over Republicans on national security. Obama has achieved that distinction by escalating the use of drones and ordering the execution of suspected terrorists, including American citizens. Those policies have led Sarah Khan to sue the Department of Defense and the CIA for the September 30, 2011 death of her 25-year-old son, Samir. Saudi native Samir Khan became a naturalized citizen after he moved as a child to Queens with his family. By most accounts he was a normal teen until the summer of 2001, when he attended a weeklong summer camp sponsored by the fundamentalist but nonviolent Islamic Organization of North America. The experience turned the religiously indifferent teen into a zealot. A few months later the September 11 attacks made him a radical. By the time his family relocated to Charlotte, North Carolina three years later, Khan had morphed into a jihadist committed to waging war against those he considered enemies of Islam.

Khan holed up in his parents’ north Charlotte basement, publishing anti-American and pro–Al Qaeda screeds. As his writings became more popular, he attracted the attention of federal authorities yet miraculously never landed on the no-fly list. In October 2009 he left Charlotte for Yemen, ostensibly to teach English. Once there, Khan fell off the radar. He resurfaced during the summer of 2010 as editor of Inspire, an online magazine that sought to recruit American Muslims to join the anti-U.S. jihad.

A year later Khan was killed by a U.S. drone strike on his convoy about 90 miles east of the Yemeni capital of Sanaa. Khan’s family took the government to task in a written statement that read in part, “Our late son Samir Khan never broke any law and was never implicated in any crime. The Fifth Amendment states no citizen shall be ‘deprived of life, liberty or property, without due process of law,’ yet our government assassinated two of its citizens. Was this style of execution the only solution? Why couldn’t there have been a capture and trial? Where is the justice?”

The radical cleric Anwar al-Awlaki, marked for death by the administration, is the other American referred to in the statement. It isn’t clear if Khan was a target or collateral damage.

Al-Awlaki was born in New Mexico but spent nearly a dozen years in his ancestral home of Yemen before returning to the U.S. to attend Colorado State University. After the 2001 attacks, he moved to the United Kingdom and eventually made his way back to Yemen, where he became involved with Al Qaeda in the Arabian Peninsula.

The government claims Al-Awlaki ­instructed Umar Farouk Abdulmutallab, the so-called underwear bomber, to blow up a plane flying to Detroit in 2009, and inspired the actions of Army major Nidal Hasan, who is being court-martialed for killing 13 people at Fort Hood, Texas in a 2009 rampage. Despite being linked to these planned attacks, Al-Awlaki was never charged with a crime. Two weeks after his death, his 16-year-old son, Abdulrahman, also an American citizen, was killed in a drone strike aimed at Al Qaeda.

Hundreds of suspected terrorists were rounded up after September 11, 2001 and imprisoned in Guantánamo Bay, only to be transferred or released later in a tacit acknowledgment that they weren’t terrorists. But when a suspected terrorist is killed, there is no do-over.

Al-Awlaki and Khan made no secret of their allegiance to Al Qaeda and their desire to wreak havoc. Khan’s articles in Inspire included “Make a Bomb in the Kitchen of Your Mom” and “I Am Proud to Be a Traitor to America.” Al-Awlaki’s blog, Facebook page and many YouTube videos were testaments to his terrorism bona fides. But the issue is not guilt or innocence. Were these American citizens accorded due process under the law?

“The Constitution ordinarily guarantees American citizens that they will not be deprived of life without due process of law,” says Jameel Jaffer, an ACLU lawyer representing the families of Khan and Al-Awlaki. “The administration has claimed the authority to carry out the targeted killing of anyone, including any American thought to be engaged in terrorism. It’s impossible to reconcile that position with the constitutional provision.”

“The Constitution guarantees due process, not judicial process,” Attorney General Eric Holder said during a speech at Northwestern University’s law school in March 2012. “Due process and judicial process are not one and the same, particularly when it comes to national security.”

Holder argues that following 9/11, Congress authorized the president “to protect the nation from any imminent threat of violent attack.” Because Al ­Qaeda operates around the world, Holder said, the rules of conventional warfare no longer apply. “The president may use force abroad against a senior operational leader of a foreign terrorist organization with which the United States is at war—even if that individual happens to be a U.S. citizen,” Holder said.

Candidate Barack Obama promised to chart a different course. Once in office, he set out to improve relations with the Muslim world, repair America’s image abroad and renounce the cowboy diplomacy that had defined foreign policy under President George W. Bush. Obama banned torture and extraordinary rendition and tried to make good on his promise to close Guantánamo and try detainees in federal civilian courts. But Congress blocked him. However, when it comes to drone strikes, the president has outpaced Bush, expanding the program, which had previously focused only on Pakistan, to include Yemen, Afghanistan and Somalia.

The Bush administration was criticized for warrantless wiretapping and indefinite detentions without charge or trial, but Obama has been given a pass for his aggressive measures. The same Democrats who railed against the prior ­administration’s policies have remained silent on Obama’s decision to ramp up drone strikes and use targeted killings.

Republicans have a different conundrum. Given their hawkishness and ­persistent claims of Obama’s weakness on war and terrorism, they can hardly complain about his overzealousness in prosecuting the war against Al Qaeda.

But the rumblings of discontent over this administration’s blank check for war are growing louder. The wrongful-death lawsuits are the most prominent example, but the U.S. also stands alone on the drone issue. In predominantly Muslim nations, American antiterrorism efforts are widely unpopular, and in 17 of 20 countries, more than half disapprove of the drone attacks.

“I used to joke, 'If they can hold you indefinitely without judicial review, why couldn’t the administration also carry out targeted killings without judicial review?’” says Jaffer. “Now that’s no longer a rhetorical device. It’s ­reality. It’s hard to imagine any more extreme claim of authority than the power to order the killing of American citizens without judicial process.”

Obama defended his policy in a September 5, 2012 interview with CNN. “I think there’s no doubt that when an American has made a decision to affiliate with Al Qaeda and target fellow Americans, there is a legal justification for us to try to stop them from carrying out plots,” he said. “It’s very important for the president and the entire culture of our national security team to continually ask tough questions. Are we doing the right thing? Are we abiding by rule of law? Are we abiding by due process?”

The U.S. established precedent for taking out an enemy leader 70 years ago with the targeted killing of Japanese naval commander Isoroku Yamamoto, who planned and executed the attack on Pearl Harbor. When Yamamoto’s plane was tracked to an island in the South Pacific, President Franklin D. Roosevelt approved the order to shoot it down.

Jaffer says that while there is no moral distinction between ordering the killing of a U.S. citizen and a noncitizen, there is a legal distinction. “Americans plainly have rights protected by the Constitution, including the right not to be deprived of your rights without due process of law,” he says. “The law generally requires that there be an imminent threat and that the use of lethal force be a last resort. Was Al-Awlaki an imminent threat or simply an ongoing threat?”

More than a year before his son’s death, Al-Awlaki’s father, Nasser, asked a judge to outline the circumstances under which targeted killing could be authorized. The case was dismissed because Nasser did not have standing to sue on behalf of his adult son. Nasser is now suing the government for wrongful death on behalf of his son’s estate.

“If this case can’t be heard, then courts are saying the political branches can decide which Americans are associated with terrorism and can be killed—and these decisions can be done in secret,” says Jaffer. “That’s an astonishing and dangerous proposition and an unchecked investment of power to a president.”

In an effort to take responsibility for each death, Obama is said to decide personally who is targeted for killing and approve every major drone strike in Yemen and Somalia. But should any president be granted such power, regardless of his judicious consideration? Any power given to Obama will be used by presidents who follow him in office. Would liberals be quiet if a President Romney made these calls? That possibility obviously concerned the president. In the weeks before the election, the administration developed rules for the targeted killing of terrorists by unmanned drones so that a new president would inherit clear standards and procedures.

But even Obama acknowledged that drone strikes are not a long-term solution to terrorism. “Our most powerful tool over the long term to reduce the terrorist threat is to live up to our values and to be able to shape public opinion—not just here but around the world—that senseless violence is not a way to resolve political differences,” he said, sounding more like candidate Obama than President Obama.

We won’t know how a different president would exercise such authority. But we do know that President Obama is unlikely to change course during his second term.