(CNN) If you want a politician to shout your grievances, Donald Trump is your man. But he's still learning to feel your pain.

The President's brusque style, an asset that helped him win the White House, complicates his next assignment -- a visit to console those wounded and traumatized by the Las Vegas massacre, a day after a trip to the Puerto Rico disaster zone.

Nothing in Trump's career as a wheeler-dealer, reality star and bulldozing outsider politician has equipped him for what will be an emotional day Wednesday of meeting survivors and first responders following the worst mass shooting in modern American history.

"We're going to pay our respects, to see the police who've done really a fantastic job in a short time," Trump said before leaving Washington.

"It's a very, very sad day for me personally."

Trump has spent the last eight months reeling from crisis to crisis, mostly of his own making, approximating the chaotic whirl that has characterized his entire adult life. The Las Vegas massacre and Hurricane Maria, however, are examples of sudden, uncontrollable crises that inevitably batter each White House, and have the capacity to define presidencies.

Such national traumas test a president's emotional depth, or at least their capacity to make people think they care.

Most potential presidents build their one-on-one game on the campaign trail in places like New Hampshire. But Trump preferred rock-style rallies where he could connect at arms length with thousands.

He wouldn't be the first president to find the moment when he is required to channel the nation's grief challenging.

JUST WATCHED President Trump leads moment of silence Replay More Videos ... MUST WATCH President Trump leads moment of silence 01:04

President Ronald Reagan wrote in a diary entry about the emotional impact of meeting relatives of Marines killed in the Beirut barracks bombing in 1983, alongside his wife Nancy.

"It was a moving service & as hard as anything we've ever done," Reagan wrote. "Sometimes widows or mothers would just put their arms around me, their head on my chest & quietly cry."

Three years later, Reagan comforted relatives of the dead crew of the space shuttle Challenger, and wrote "all we could do was hug them & try to hold back our tears."

Each President since has dealt with tragedy and sometimes the consequences of their orders to send young men to war. George W. Bush, for example, regularly met wounded warriors from Afghanistan and Iraq.

In 2012, it fell to Barack Obama to preside over a wrenching memorial service for the young children killed in a horrific massacre at Sandy Hook elementary school in Newtown, Connecticut.

A grief-stricken silence hung like a pall over Air Force One that night, as the president and his entourage returned to Washington after a traumatic few hours in the company of parents whose beloved kids had been ripped away.

On Wednesday, Trump must offer compassion and sympathy to surviving victims while uniting a nation polarized by his own presidency and the bitterly contested issue of gun control and rights.

In his eight months as President, he has shown himself more at home in the less formal aspects of the presidency, notably waging Twitter wars, than he has in some of the ceremonial aspects that come with the job.

All winning candidates face a huge adjustment they assume the presidency, a job shaped by two centuries of protocol. For Trump, who had no previous political, governmental, military or diplomatic experience, the transition was especially stark.

But critics also accuse the President of using the office as a prop for his own ego -- a trait in evidence on Tuesday in Puerto Rico.

What had been billed as a chance for Trump to see the devastation himself turned into a cheerleading session for a relief effort that some news reports suggest has been plagued by delays and logistical snarls.

It was just the latest example of Trump's struggle to sometimes hit an appropriate tone and his tendency to whip up controversy with his awkward rhetorical style.

Meeting local officials, Trump made a a jarring joke about the island putting the federal budget "a little out of whack." He noted that the preliminary death toll of 16 on the island did not measure up to that of a "real catastrophe" like Hurricane Katrina in 2005. He also boasted about his administration's response to Hurricane Harvey in Texas and touted his achievement in cutting the cost of the F-35 fighter jet, issues that are hardly relevant to Puerto Rico's plight.

JUST WATCHED Trump's full remarks on Puerto Rico response Replay More Videos ... MUST WATCH Trump's full remarks on Puerto Rico response 13:42

On the way home on Air Force One, the President gushed about the praise he had received for his handling of the disaster.

"We've only heard thank yous from the people of Puerto Rico," Trump said.

"I think it meant a lot to the people of Puerto Rico. ... It's the first time that a sitting President has done something like this."

While several local officials, including Gov. Ricardo Rosselló, repeatedly praised the President's role, possibly as a way of winning his support for the long haul ahead, he did not convince everyone.

San Juan Mayor Carmen Yulín Cruz, who has publicly sparred with Trump, said that a meeting she had with the White House staff was more useful than the session she participated in with the President on Tuesday.

"I would hope that the President of the United States stops spouting out comments that really hurt the people of Puerto Rico, because rather than commander in chief he sort of becomes miscommunicator in chief," Yulín Cruz told CNN.