Gregory Korte

USA TODAY

WASHINGTON — With his tenure in office marked by terror attacks and mass shootings, President Obama has reached a sad but remarkable milestone in his presidency: He has ordered the lowering of the nation's flags to half-staff more often than any president in history.

On Sunday, Obama extended that unenviable streak even further, ordering all flags at federal buildings and ships at sea to be flown at half-staff to honor the 49 victims of the Orlando nightclub shooting.

Those flags will remain at half-staff until sunset Thursday, meaning that the nation will spend most of National Flag Week — proclaimed by Obama in a separate order last Friday— with the stars and stripes in a mournful pose.

Since 2009, Obama has issued 66 proclamations to fly the flag at half-staff, exceeding President George W. Bush's 58 and Bill Clinton's 50, according to a USA TODAY analysis of presidential proclamations.

Annual observances such as Memorial Day and Pearl Harbor day have contributed to that total, as have the deaths of notable public figures like Sen. Robert Byrd, Sen. Ted Kennedy, former first lady Nancy Reagan and Supreme Court Justice Antonin Scalia.

But it's a spate of national tragedies — from the Fort Hood shooting that claimed 13 lives in 2009 to the most recent carnage in Orlando — that have distinguished the Obama presidency. Fourteen proclamations honoring the victims of those tragedies have accounted for 79 days with the flag over the White House at half-staff, more than half of the 158-day total under Obama.

"The lowering of the flag in an order from the president of the United States is a symbolic expression of national mourning, and it certainly is a way, symbolically, to demonstrate that the country is united in our support for a community that's mourning," White House Press Secretary Josh Earnest said Wednesday. "I think what we also see is that over the course of generations, that symbolism is expressed in different ways."

Presidential scholars say Obama's use of such proclamations show an evolution of the presidential "soft power" as comforter in chief into a more formal and visible display of national sorrow.

"Especially during partisan times, when there's polarization among the American people, presidents are seeking a way to find a mechanism to unify people," said Brandon Rottinghaus, a professor at the University of Houston who tracks presidential proclamations. "This allows him to connect on an emotional level rather than a political or a policy level."

14 mass shootings, 14 speeches: How Obama has responded

Like executive orders, proclamations have the force of law — but are most often used to honor constituency groups or recognize special events. But that doesn't make them unimportant, Rottinghaus said. "It's a significant role that the framers intended the presidency to be, which is kind of a figurehead and the true representative of the nation," he said.

But flags are lowered so often that it's becoming difficult for the White House to know where to draw the line. After a lone-wolf terrorist killed five servicemen at a military recruiting station in Chattanooga last year, Earnest struggled to explain why it took the president five days to order flags to be flown at half-staff.

"I don't have a lot of insight to provide to you in terms of that decision-making process," he said at the time. "But I will note that the proclamation was issued right around the same time that the president was delivering a eulogy for the five servicemembers who were killed in East Tennessee last week."

The American Legion, a veterans service organization often looked to for flag etiquette advice, said it's not concerned about the increasing number of half-staff days proclaimed by the president. "That's his prerogative,. We’re not going to question the reasoning," said deputy director Mike Buss. What does concern him, however, is that individuals are increasingly lowering the flag for more personal reasons not proclaimed by the president.

Eisenhower's regulations

Before President Dwight Eisenhower, the lowering of flags was a more haphazard process, with different departments making their own decisions and little consistency. After Eisenhower ordered flags be lowered to half-staff for 30 days to honor Chief Justice Fred Vinson — a duration some thought too long — Eisenhower signed Proclamation 3044 to bring some clarity to the process.

Presidents and former presidents would get 30 days. Vice presidents, chief justices and House speakers would get 10. Associate justices, sitting Cabinet members and the secretaries of the Army, Navy and Air Force would have the flag lowered until their burial. (President Nixon amended that last group in 1969 to exclude the service secretaries and add congressional leadership.)

"It was a logical thing to do to come up with an number days so you knew what to do," said John Hartvigsen, a flag historian at the Colonial Flag Foundation and the president of the North American Vexillological Association, which is dedicated to the scholarly study of flags. "In days past, I looked at that and said, this makes sense. But anymore I’d have to reconsider it. It’s taking mourning back to a Victorian view of how many days do you wear black gloves to mark the death of a loved one."

But even Eisenhower gave himself and his successors the flexibility to lower flags on other occasions: "In the event of the death of other officials, former officials, or foreign dignitaries, the flag of the United States shall be displayed at half-staff in accordance with such orders or instructions as may be issued by or at the direction of the President, or in accordance with recognized customs or practices not inconsistent with law."

For many decades afterward, presidents more or less followed those guidelines, even as they used the flag as a way to honor everyday servicemen who died in the line of duty. President John F. Kennedy lowered the flags for the 129 crew members of a sunken nuclear submarine, the U.S.S. Thresher, in 1963, and President Jimmy Carter similarly honored eight servicemen who died in a failed rescue attempt of the Iranian hostages in 1979.

It was President Ronald Reagan who perhaps first understood how to use the tools of the modern presidency unify the country during times of national tragedy. He lowered flags after the Soviet Union shot down a Korean Air Lines flight on which a congressman from Georgia was a passenger, the Space Shuttle Challenger exploded, and the U.S. embassy in Beirut was bombed. President Bill Clinton continued that tradition, using a lowered flag to remember the victims of a series of terrorist attacks, domestic and foreign, in Oklahoma City, U.S. embassies in Africa, the Khobar Towers in Saudi Arabia and the U.S.S. Cole.

President George W. Bush marked the Sept. 11, 2001 terrorist attacks with six days — but then extended it for another six days. He then signed another proclamation and took part in a ceremony at Camp David to restore the flag to full-staff. Bush was also the first to use the flag to mark tragedies caused by natural disasters, including Indian Ocean tsunamis and Hurricane Katrina in 2005.

Obama has continued those trends, and some wonder whether there's a limit to how often the nation can be expected to pay attention to the many commemorations.

"It’s proliferated in the last few years," Hartvigsen said, not just because of Obama, but because of Congress. In addition to Memorial Day (during whiuch the flag is to be flown at half-staff only until noon), Congress has over time added commemorations for Korean War veterans, the 9/11 anniversary, Pearl Harbor Day and separate memorials for police and firefighters.

And increasingly, flags are flying at half-staff for two simultaneous commemorations. The proclamation lowering flags for the victims of the San Bernardino shooting last December overlapped with National Pearl Harbor Remembrance Day on Dec. 7. A resolution for the Roseburg, Ore., community college shooting overshadowed a previously scheduled commemoration for fallen firefighters last Oct. 4. And in 2005, President George W. Bush signed two proclamations the same day, lowering flags for both Chief Justice William Rehnquist and the victims of Hurricane Katrina.

"The question is, how do we appropriately do it so we don’t overdo it, because when you overdo it it loses its meaning and significance," Hartvigsen said. If the flag is flying at half-staff, no one should have to ask why, he said.

The Orlando shooting, he said, passes that test. "If somebody walks out today and sees the flag at half-staff, they know why the flag is at half-staff," he said. "The nation is grieving. We’re hurt. We were all attacked when those 49 people were killed."

In all, Obama has spent almost 6% of his presidency living under a White House flag at half-staff. But Earnest said those darker days shouldn't define the Obama years.

"These kinds of tragedies that we’ve encountered have prompted us to mourn, but they've not set us back," he said. "The kind of perseverance and resilience we’ve seen in those communities that have been scarred by violence have been an inspiration to all of us."