This piece is part of a series on Obama’s legacy that The Huffington Post will be publishing over the next week.

WASHINGTON ― A little more than halfway through his presidency, Barack Obama visited the National Defense University in Washington, D.C., to give a speech outlining how he would restrict his own power to use drones to target and kill individuals far from traditional battlefields.

Obama acknowledged public concern around drone strikes and announced stricter standards on their use. The new rules, Obama said, codified “clear guidelines, oversight and accountability.” But they were policy, not law. They didn’t bind him and couldn’t bind future presidents. Americans, it seemed, would have to trust that the president and his successors would follow the rules he created.

Obama campaigned on ending the broad and legally hazy counterterrorism tactics of his predecessor. But over the past eight years, he has expanded presidential war-fighting powers, not scaled them back. He has authorized six times as many covert drone strikes in Yemen, Pakistan and Somalia as former President George W. Bush, according to non-governmental organizations’ estimates. He has overseen the creation of a massive surveillance program and deployed the military to fight new wars without congressional authorization.

The 2013 drone policy guidance is an instructive example of Obama’s failure to rein in presidential war-making powers. Obama claimed the measure ensured sufficient oversight of assassinations abroad. But when a Freedom of Information Act lawsuit forced the Obama administration to release a redacted version of the drone rulebook last year, civil liberties advocates said it did little to constrain the president’s power to decide who lives and who dies.

“It is riddled with ambiguities and loopholes,” said Jameel Jaffer, the author of a book on the Obama administration’s legal justification of its targeted killing program. There are exemptions for some strikes conducted by the CIA, and many of the standards laid out in the rule book are subject to interpretation. And because the rulebook is policy, not law, future presidents have no obligation to adhere to it.

It is riddled with ambiguities and loopholes. Jameel Jaffer, on Obama's drone rulebook

The month after Obama’s landmark 2013 drone speech, The Guardian published its first stories based on leaks from former National Security Agency contractor Edward Snowden. Again, the president defended a controversial counterterrorism program that was launched by his predecessor and expanded by his administration.

“It’s important to recognize that you can’t have 100 percent security and also then have 100 percent privacy and zero inconvenience,” Obama said in June 2013. “In evaluating these programs, they make a difference in our capacity to anticipate and prevent possible terrorist activity.”

When faced with new threats abroad, Obama has bypassed Congress several times and deployed the military using strained legal rationale. When the Obama administration led a NATO coalition against former Libyan dictator Muammar Gaddafi in 2011, it did so without congressional authorization.

Obama again bypassed Congress in 2014 and ordered airstrikes against Islamic State fighters in Iraq and Syria. The ongoing daily airstrikes are covered, the White House claims, under the war authorization Congress passed in 2001 to fight the groups that planned the Sept. 11 attacks. The Islamic State did not exist in 2001.

John Moore/Getty Images President Barack Obama has authorized six times as many covert drone strikes in Yemen, Pakistan and Somalia as former President George W. Bush.

And although Obama has moved aggressively to transfer as many prisoners out of Guantanamo Bay as possible in his final days in office, human rights advocates charge that he should have acted more decisively to close the prison in his early years in office, before Congress stuffed provisions into must-pass legislation to block its closure.

“I will never forgive @POTUS for failing to close GTMO when he had the chance,” tweeted Alka Pradhan, who represents accused Sept. 11 co-conspirator Ammar al-Baluchi.

When Obama has sought to make a deliberate break from Bush-era policies, he has resisted holding anyone accountable for them. In his first days in office, he ended the Bush-era torture program but declined to endorse prosecuting those responsible. Years later, he actively fought the public disclosure of some of the most damning parts of the Senate Intelligence Committee’s report on the torture program.

Last month, Obama traveled to the MacDill Air Force Base in Tampa, Florida, to deliver his final speech on counterterrorism. The day before that speech, his administration had released a 61-page memo outlining its legal justifications for the use of force. Like the 2013 drone rule book, it was a bid at transparency that left a lot of questions unanswered and has no binding effect on the next administration.

In the speech at MacDill, Obama ran through a list of reminders about American values — a message that could only be directed at President-elect Donald Trump, who has vowed to ban Muslims from traveling to the U.S., to reinstitute torture, and to send Americans to Guantanamo Bay, where people are detained for years without charge or trial. The U.S., Obama said, is “a country where people can criticize their president without fear of retribution and where there are no religious tests.” It is “a country where you’re judged by the content of your character rather than what you look like, or how you worship, or what your last name is, or where your family came from ... a nation that won world wars without grabbing the resources of those we defeated.”

Obama spent years asking the American public to trust him with unprecedented war-making authority. But his parting words to the country were an implicit warning that his successor shouldn’t be trusted with those very same powers.