WASHINGTON >> President Barack Obama will fly to Dallas “early next week,” aides said late today — cutting short a visit to Spain, and adding the police ambush to a litany of tragedies that have merited his attention.

“The president has accepted an invitation from Dallas Mayor Mike Rawlings,” White House press secretary Josh Earnest announced from Poland, where Obama is attending a NATO summit. “Later in the week, at the White House, the president will continue the work to bring people together to support our police officers and communities, and find common ground by discussing policy ideas for addressing the persistent racial disparities in our criminal justice system.”

This will be Obama’s fourth trip to Texas in the role of consoler-in-chief.

Fort Hood earned two of those visits. Just 10 months into his presidency, an Army psychiatrist inspired by Muslim terrorists, Maj. Nidal Hasan, gunned down 13 people and wounded 30 others. In April 2014, Obama returned to honor three victims of another shooting spree.

He also attended a memorial for the 15 victims of a fertilizer plant explosion in West, Texas, in April 2013.

At the NATO summit, world leaders showered Obama with condolences today over the Dallas police ambush.

That included President Ashraf Ghani of Afghanistan, whose sympathy was “particularly poignant,” said Obama national security aide Ben Rhodes, given that country itself “has suffered enormous violence and loss of life.”

Obama awoke to news of the Dallas attacks as he arrived in Warsaw late Thursday, quickly condemning the violence as “despicable” and vowing a robust federal response. Today, he called for national unity—but also expressed frustration that Congress has consistently turned away his proposals to tighten access to guns.

“When people are armed with powerful weapons, unfortunately, it makes attacks like these more deadly and more tragic,” he said. “In the days ahead, we will have to consider those realities.”

He ordered flags lowered to half-staff through sunset on Tuesday in honor of those shot in Dallas. From Warsaw, he got updates on the investigation in calls with Dallas Police Chief David Brown and Attorney General Loretta Lynch. He offered condolences on behalf of the country to Brown.

“The entire country is grieving alongside the people in Dallas,” Earnest said.

In Washington, some of the president’s conservative critics were accusing him of setting the stage for such attacks by pointing blame at police in previous incidents, and sympathizing with Black Lives Matter and other groups that complain about racial bias in policing.

Rep. Roger Williams, R-Texas, asserted that “the spread of misinformation and constant instigation by prominent leaders, including our president, have contributed to the modern day hostility we are witnessing between the police and those they serve.”

Obama and Lynch emphasized that there is never any justification for violence directed at police.

In New York, Homeland Security Secretary Jeh Johnson stood with law enforcement at police headquarters in a show of solidarity. He echoed the administration’s balanced message that violence is never justified, though that shouldn’t preclude legitimate examination of police practices.

“Last night’s killer acted with a depraved misbelief that the murder of police officers solves a problem,” Johnson said. “Just like last night’s killer does not represent all those who seek to bring about change, any police officer who engages in excessive force does not represent all those in law enforcement; far from it.’

Like the president, Earnest emphasized the grief and solidarity with police and the community. He also underscored the president’s frustration with the stalemate over gun policy. To Williams’ criticism, he said, “People can judge for themselves.”

“Acknowledging the reality of some of the persistent disparities in our criminal justice system, and vowing to confront them, is not at all an expression of criticism or a lack of support for the vast majority of men and women in law enforcement who do an outstanding job,” Earnest said. “Too many innocent lives have been claimed because of the easy access that people have to guns, in some cases guns that were never intended to be on city streets,” Earnest said. And he said, “The president is pained that our country’s divisions have prevented as much progress as he would like to see on these persistent racial disparities in our criminal justice system.”

The administration has refrained from questioning the use of a robot-delivered explosive by police to kill the sniper.

“The president certainly does believe that law enforcement agencies should have the firepower necessary to protect the community,” Earnest said.