Dick Cheney has no problem criticizing President Obama. In a recent Wall Street Journal commentary, the former vice president and his daughter Liz blasted Obama's handling of the wars in Iraq and Afghanistan. "Rarely has a U.S. president been so wrong about so much at the expense of so many," they wrote. Former President George W. Bush, however, has "vowed not to criticize his successor and does not have a comment" about what, if anything, the United States should do in Iraq, according to a statement from his spokesman.

Compared with Bush, Bill Clinton has taken on a more activist role since leaving the White House — starting a charitable foundation, writing books and giving rousing endorsement speeches. But he has also joined his successors in crisis moments, as when he and Bush jointly appealed for Haiti relief in 2010. Meanwhile, Obama and his predecessors have appeared together at presidential library dedications and flown together on Air Force One.

For most of American history, former commanders in chief have been impressively collegial with their successors and with each other — it's "The Presidents Club," as a recent book dubbed it, after all, not "Fight Club." But presidential retirement wasn't always so chummy.

In the years shortly before and during the Civil War, the traditional post-presidency silence proved too difficult to keep — and President Abraham Lincoln suffered the consequences. The battle between Lincoln and the former presidents alive at the time is a critical but little-heralded story of the American Civil War and a vast departure from the history of the post-presidency.

As America slid toward disunion and war, the 1860 election pushed the former presidents off the sidelines. Franklin Pierce, who left the White House in 1857, tried to recruit his former secretary of war, Jefferson Davis, to run for president. John Tyler, who had been out of office for 15 years, wanted the job for himself and authorized his friends to put his name forward if the opportunity arose. (It did not.)

When the Democratic Party collapsed into Northern and Southern factions during the campaign, Pierce, Tyler and James Buchanan supported John C. Breckinridge, the nominee of the Southern Democrats; Martin Van Buren supported Stephen Douglas, chosen by the party's Northern wing. Tyler and Van Buren proposed that Democratic electors band together to deny Lincoln the presidency by voting for whichever of his opponents had the most support.

Millard Fillmore, the last president who was neither a Democrat nor a Republican, supported the Constitutional Union Party, mostly former Whigs running on a platform of national harmony.

Despite their political differences, the former presidents all saw the role of president as conciliator in chief, whose main objective was to keep the union together, generally by making concessions to the South. They regarded the election of Lincoln, with his firm commitment to end the expansion of slavery, as menacing the presidency and the union itself.

As divisions over slavery worsened, people throughout the country wrote to the former presidents, urging them to come together to forge a compromise. Pierce nearly succeeded in convening such a meeting but was thwarted by Van Buren, who saw it as an attempt to undermine Lincoln.

When Lincoln took the oath of office in 1861, Buchanan joined the circle of former presidents, elevating their number to five. Perhaps no one hated the post-presidency more than he did. He was routinely blamed for the crisis, and his mailbox filled with death threats. Buchanan, along with his predecessors, urged Lincoln to accept a compromise on slavery. (Most supported extending the Missouri Compromise line to the Pacific Ocean.)

Buchanan's first public comments on the war condemned military officers who had violated their oaths to join the Confederates. He initially supported Lincoln, arguing that his successor had simply followed his policies — hoping that Lincoln's success would vindicate his own presidency. Buchanan's defense of his administration, published after the war, became the first in a now ubiquitous genre: the post-presidential memoir.

When Confederates fired on Fort Sumter, the former presidents were quick to take sides. Perhaps Fillmore put it best, addressing a Union meeting at Buffalo's Metropolitan Theater the day after Lincoln's request for troops: "We have reached a crisis in the history of this country when no man, however humble his rank or limited his influence, has a right to stand neutral." For Fillmore, this meant raising a New York militia unit, the Union Continentals of Buffalo. Their duty was to drum up enthusiasm for the war and escort departing soldiers to the train station — along with a somber corollary duty, to accompany many of those same boys from the depot on their way to be buried.

When Britain was poised to enter the war on the Confederate side, after the U.S. Navy boarded a British vessel, Fillmore wrote Lincoln six pages of recommendations; assure Britain that no slight was intended and request binding arbitration, he advised.

Van Buren likewise stood by Lincoln, calling the attack on Fort Sumter "a treasonable attempt to overthrow the federal government by military force" and encouraging young men to join the military.

As Tyler relentlessly pushed Virginia from the Union, Pierce condemned Lincoln's call to arms. The South, he believed, should be permitted to leave peacefully if it could not be persuaded to stay. Pierce labored tirelessly throughout the war to elect candidates who opposed Lincoln. He remained a critic of the president, especially on civil liberties, and publicly fought with the administration, which accused him of treason. When Jefferson Davis' Mississippi home was captured by Union forces, Pierce's secret correspondence with the Confederate president was revealed, sealing his unpopularity. Despite their fierce political disagreements, Pierce, who had lost his only surviving son in a train accident on the way to his inauguration, wrote Lincoln a heartfelt note after the death of the president's 11-year-old son, Willie, in 1862.

With the Emancipation Proclamation, Lincoln broadened the Union's objective from reunion to the destruction of slavery. He then lost the support of Fillmore and Buchanan, whose sole condition for peace had been status quo antebellum. Lincoln believed that while America should return to what it had been geographically, it could never return to being "half slave and half free."

This proposition was tested in the campaign of 1864: Democrats considered nominating Pierce as well as Fillmore. Those two ex-presidents, along with Buchanan, supported George McClellan, actively campaigning against Lincoln in a way that made their efforts four years earlier seem tame. (Tyler and Van Buren had died in 1862, while the fate of the country was very much in doubt.)

But Lincoln achieved what none of them could: re-election, which had eluded his predecessors for 32 years. The war continued until Confederate surrender and passage of the 13th Amendment.

On the night of Lincoln's death, a mob confronted Pierce at his home, which wasn't displaying a flag in honor of the president's passing, but he assured them that his sorrow matched theirs. "The magnitude of the calamity," he said, "in all its aspects, is overwhelming." In a letter to a friend, Buchanan wrote that "I deeply mourn his loss from private feelings, but still more for the sake of the country." Fillmore wrote to Mary Lincoln, offering his home as she traveled with the funeral train through Buffalo, where he had hosted the Lincolns four years earlier on their way to Washington.

After the Civil War, it took generations for former presidents to stop seeking political office once they'd left the Oval. After leaving the White House in 1869, Andrew Johnson became a senator from Tennessee. Grover Cleveland, who lost his first attempt at re-election, in 1888, returned to office in 1893. Theodore Roosevelt, "the man in the arena," was not suited to retirement, unsuccessfully running against his hand-picked successor, William Howard Taft, after Taft's first term.

Calvin Coolidge may have inaugurated the current era of former presidents getting along, through his roles as philanthropist, civic volunteer, businessman and, of course, memoir writer. Herbert Hoover fulfilled all of these and added presidential troubleshooter to the list, helping save millions of Europeans from starvation at the request of Harry Truman and finding inefficiencies in government under Dwight Eisenhower.

A series of relatively young and healthy chief executives in recent years ensures a steady supply of former presidents for the foreseeable future. We've come a long way since Fillmore thought it "a national disgrace, after having occupied the highest position in the country, that our presidents should be cast adrift, and perhaps be compelled to keep a corner grocery for subsistence." And since Pierce wondered: "After the White House, what is there to do but drink?"

Whatever opinions Americans have of former presidents, we should be grateful that, in our lifetimes, we haven't seen another crisis of the magnitude of the Civil War to bring them crashing back into politics in a big way.

Chris DeRose, a visiting assistant professor of law at the Arizona Summit Law School, is the author of "The Presidents' War: Six American Presidents and the Civil War That Divided Them." He wrote this article for the Washington Post.