Many saw President Harry Truman as a man of plain speech — straight shooting and unvarnished, sometimes to the point of rudeness. During the 1948 presidential campaign, audiences goaded on his attacks on the Republican Congress with, "Give 'em hell, Harry!"

But plain speech can get you only so far as a manager. Truman knew it, and acted accordingly. Those who worked with Truman remember him as a man of kindness, diplomacy, learning — and even tact.

In the 2003 book "HST," a collection of interviews with Truman's associates edited by Steve Neal, the members of the Truman White House recalled that their boss insisted on an atmosphere of open communication.

Dean Acheson, Truman's secretary of state from 1949 to 1953, said he and Truman discussed every problem from the beginning so that each always knew the other's opinions.

"It was a great thing between Mr. Truman and me," Acheson said. "Each one understood his role and the other's. . . . I never thought I was president, and he never thought he was secretary."

Making clear who was president was Truman's main challenge when he inherited the presidency on the death of Franklin Roosevelt. Truman didn't even want to be vice president when Roosevelt tapped him as a running mate in the 1944 campaign. He was happy being a senator from Missouri, as he had been for 10 years.

Truman was in office less than three months when Roosevelt died, and World War II was in its final stages.

To make the office his own, Truman immediately had to assert his authority over a White House filled with Roosevelt men.

Some of these, such as Secretary of Commerce Henry Wallace, got the ax. But Truman knew he'd need the advice of those with experience. Remaining Roosevelt holdovers noticed some positive changes with the new boss, such as his respect for the chain of command. Roosevelt commanded low-level employees to do his bidding without telling their superiors, but Truman believed in the structure of authority.

That doesn't mean he never had contact with the underlings. Acheson also recounted a disagreement he had with young employee Bert Marshall about a line in a speech for Truman. To Marshall's surprise, Acheson urged him to take the issue to Truman.

"He did, and the president was very nice to him, but he decided I wasn't wrong," Acheson said. Still, Marshall was so impressed with the courteous reception that "he was working 17 times harder than before."

Former research director Ken Hechler, who in 1980 wrote a memoir of his experience called "Working With Truman," likewise remembered Truman's surprisingly respectful treatment of his political opponents. Hechler was a registered Republican when Truman employed him.

"For a man who could give the most rip-roaring, convincing stump speech on the superiority of the Democratic Party, Truman had many close Republican friends," Hechler wrote.

The generosity toward opponents played out in Truman's policies as well. After World War II, many policymakers wanted to punish Germany and Japan for their sins by driving them into penury. Truman's key support for the Marshall Plan paved the way for turning those countries into peaceful, prosperous allies.

Truman had a similar policy of heading off trouble in his White House. In "HST," former appointments secretary Matthew Connelly noted there were no hidden conflicts among the White House staff.

"If any conflicts developed, the president would take care of them automatically," Connelly said. "He wanted no part of that. He wanted a family."

To keep everything humming, Truman held a staff meeting every morning that followed a dependable protocol. Everyone was arranged in a semicircle around Truman. Starting at his left, Truman went around the room giving everyone a chance to speak about the issues in his department.

"If there were any differences of opinion, we would bring it up then and settle it," Connelly said.

Truman was willing to listen to anyone's opinion, even when it was diametrically opposed to his. But he couldn't put up with challenges to his authority. He knew that the smooth functioning of the state depended on the respect for his position. That belief overrode even his strong code of personal loyalty.

One person who learned that the hard way was Hugh Fulton, who worked for Truman while Truman served in the Senate. The day after Roosevelt's death, Fulton knocked on the new president's door in search of a job. As Truman's daughter, Margaret, wrote: "Poor Mr. Fulton was suffering from what Dad calls 'Potomac fever.' . . . Dad soon learned from friends that Mr. Fulton was telling everyone in Washington that he was going to be acting president — the implication being that Harry S. Truman did not have the talent to do the job. Although they parted amicably that morning, Mr. Fulton was never offered an official post at the White House."

Getting too big for your britches was the easiest way to get fired by Truman, especially given the decisions that Truman had to make once he took office. In the first six months of his presidency, Truman helped found the United Nations, watched the surrender of Germany, helped determine at the Potsdam Conference the shape of the postwar world, and authorized the bombings of Hiroshima and Nagasaki. It was no time to have to worry about office politics.

By the 1948 election — after he'd made still more historic decisions, such as desegregating the military and recognizing Israel — Truman had acquired a more presidential stature. Yet his popularity with the public still wasn't great.

Communication was again the issue. If Truman's subordinates agreed on one thing, it was that he was lousy at giving prepared speeches. As early as the 1944 campaign, some noticed he was much better at speaking off the cuff, as he did with staff and friends.

In 1948, the crew dreamed up the famed whistle-stop tour. Truman traveled the country by train and made impromptu speeches to Americans of every stripe.

The strategy worked. Truman confounded pollsters and the press, and was elected president in his own right.

BY AMY REEVES