WASHINGTON -- President George W. Bush spoke with his military commander in Iraq nearly every week.

President Barack Obama was so deeply involved in military operations that his first three Defense secretaries all complained, sometimes bitterly, about what they considered White House micromanagement.

In nearly five months in office, President Donald Trump has yet to meet or speak with either his Iraq or Afghanistan commander, even as his administration weighs deeper and longer-term involvement in both conflicts and asks Congress for a vast increase in defense spending.

Trump's hands-off approach to America's longest wars demonstrates how much control his administration has entrusted to Defense Secretary James N. Mattis, a retired four-star Marine general, and commanders on the ground.

Senior Pentagon officials and military officers who often chafed under Obama's centralized decision-making have welcomed the shift, saying it has freed them to carry out operations based on military, and not political, considerations.

But it also raises concerns that Trump has given too much latitude to the Pentagon, which already has been accused of more indiscriminate bombings than in the past, causing an increase in civilian casualties.

GUANTANAMO BAY NAVY BASE, Cuba -- On the last day of May, soldiers practiced moving a prisoner from the sprawling Detention Center Zone across the bay to a flight leaving the island, something guards had actually done for nearly 200 captives during the presidency of Barack Obama.

Then Army guards turned around and conducted a drill of a Detainee Reception Operation, the no-nonsense mission of meeting a U.S. plane delivering a new, shackled prisoner to the wartime prison, something that hasn't happened here since 2008.

It's five months into the presidency of Donald J. Trump and, in the absence of a new policy, Obama's executive orders to hold review boards and close the wartime prison still govern here. Commanders are guided by a 2009 Defense Department study on how to treat the current 41-captive population. But everyone has heard Trump's campaign promise to full Guantanamo "with some bad dudes." So two-way planning is prudent.

"I have no specific tasking. I have no tasking to plans. I have no planning requirement specifically," said the prison commander Navy Rear Adm. Edward Cashman in his first talk with reporters since assuming command of the 1,500 men and women who serve in Joint Task Force Guantanamo on April 7.

His guard force commander, Army Col. Stephen Gabavecs, added: "There's been nothing come down in an executive order that's changed or anything else at this point in time."

A key federal official who helps adjudicate claims by veterans who say they were exposed to Agent Orange has downplayed the risks of the chemical herbicide and questioned the findings of scientists, journalists, and even a federal administrative tribunal that conflict with his views.

Jim Sampsel, a lead analyst within the Department of Veterans Affairs' compensation service, told a VA advisory committee in March that he believes much of the renewed attention to Agent Orange—used during the Vietnam War to kill brush and deny cover to enemy troops—is the result of media "hype" and "hysteria," according to a transcript of the meeting released to ProPublica.

"When it comes to Agent Orange, the facts don't always matter," said Sampsel, himself a Vietnam veteran who also handles Gulf War-related illness questions. "So we have to deal with the law as written."

Part of Sampsel's job entails reviewing evidence to determine whether a veteran or group of veterans came in contact with Agent Orange outside of Vietnam. By law, veterans are presumed to have been exposed to Agent Orange if they served or stepped foot in Vietnam; they have to prove exposure if they served at sea or in another country during the war. They also must have a disease that the VA ties to exposure to the herbicide.

"From my point of view, I will do anything to help veterans, any legitimate veteran, and I've done it plenty of times," he told the Advisory Committee on Disability Compensation, a group that advises the VA. "Unfortunately when it comes to this Agent Orange, we have to have a lot of denials."

Sampsel also offered a window, for the first time, into ongoing internal deliberations at the VA about adding new diseases to the list of those connected to Agent Orange exposure. He suggested that, despite increasing evidence tying the herbicide to hypertension, or high blood pressure, the VA is not going to extend benefits to veterans with that condition.