Their rivalry was about more than a few personality-driven leadership elections - it traced the evolution of the Democratic Party. Dingell, who died Thursday, emerged in the mid-1950s from the party's union-dominated heyday, anchored across the Midwest, particularly the Detroit region he so loved and represented for nearly 60 years in Congress.
Pelosi's rise through the leadership ranks signaled the Democratic shift into a coastal liberal coalition made up of minorities and urban professionals in large cities like her hometown of San Francisco, with its 21st century technology start-ups.
Pelosi, having made history as the only female House speaker, clearly won those debates on the party's future - the nearly 70 Democrats from just two states, California and New York, represent almost 30 percent of her caucus.
"He represented, at that time, what was the innovation capital of our country, the American automobile industry. And he rode that out with all the loyalty in the world to that, even as times had changed. The change agent for that was Nancy Pelosi," Rep. Anna Eshoo, D-Calif., one of Pelosi's best friends who served under Chairman Dingell on the Energy and Commerce Committee, said Friday.
Eshoo and dozens of lawmakers lined up Friday just off the House floor to sign a memorial book for Dingell's family.
But the push toward green-energy jobs came at a political cost in Dingell's Rust Belt earlier this decade, leaving Democrats deep in the minority. Only after a carefully managed 2018 recruiting season did the party break through again in the heartland, capturing a dozen seats from Republicans across the Midwest en route to a 40-seat gain that propelled Democrats back into the majority.
Now, the old Pelosi-Dingell battles are playing out with other characters. Pelosi is again refereeing an internal dispute over how hard to push toward sweeping action to counter climate change versus preserving the old hard-hat jobs of the manufacturing economy. And this time around, she seems to be urging a cautious approach as an upstart generation of liberal Democrats demands action now on the "Green New Deal," which she referred to as the "green dream or whatever they call it."
These Democratic skirmishes began in the 1980s when Dingell ruled his committee with an iron fist.
His oversight hearings, staring down government officials or industry titans, were legendary. "You never wanted to be there raising your right hand on the wrong side of the law, with a big pot of coffee, by design, that was on that table. Because he wasn't going to let you leave early," recalled Rep. Fred Upton, R-Mich., a Dingell friend who chaired the panel for six years this decade.
Early in her career, Eshoo received a call letting her know that Dingell had appointed her to a conference committee of House and Senate negotiators on a key piece of legislation. Eshoo only halfheartedly thanked him.
"After all, it is my bill," Eshoo told Dingell. He told her his only requirement was that she promise to vote with him on other agenda issues, a request she rejected.
"Well my dear," he replied, "you will not be a conferee." Dingell hung up.
Rep. Jan Schakowsky, D-Ill., a Pelosi ally who also serves on the committee, said his death marked the passing of a bygone era of chairmen who wielded more power than House speakers. But Dingell, even as liberals pushed the Clean Air and Clean Water bills out of his committee and into law, never lost his sense of duty to the House.
"The end of an era for the reverence of this institution," Schakowsky said, "it's functioning by regular order, it's functioning with bipartisanship and compromise, and committee power where chairmen have a lot more influence as well. I think that will be missed."
The rivalry grew more personal in the late 1990s as Pelosi began a long campaign for a top leadership post, running against one of Dingell's closest friends, Rep. Steny Hoyer, D-Md., who is now majority leader. Dingell gave his full support to Hoyer, whose alliances have long run closer to unions and centrist Democrats.
By 2002, when redistricting pushed Dingell into a primary versus another Democratic incumbent, Pelosi threw her support to Dingell's opponent, Lynn Rivers. He won, but she eventually defeated Hoyer and in January 2003, Pelosi became the first woman to ever lead a congressional caucus and Hoyer settled in as her No. 2.
When Democrats claimed the majority after the 2006 midterms, Pelosi called combating climate change her "flagship issue" as speaker. Back at the helm of the committee responsible for handling the issue sat her old adversary - Dingell.
So Pelosi created a special committee to handle the issue, installing her friend, then-Rep. Edward Markey, D-Mass., as the chairman. "That shifting of the policy plates of the earth brought about the Dingell-Waxman challenge," Eshoo said, recalling an epic battle for committee chairman after the 2008 elections.
Then-Rep. Henry Waxman, D-Calif., defeated Dingell, who was ill and in a wheelchair during that contest as dozens of younger Democrats wanted action on the climate issue.
"Fred, don't cry for me," Dingell told Upton later that day, according to Upton's recollection. "He moved on, he learned real quick that when you have a loss, you can't let it plague you," Upton said.
He wasn't happy, but he played loyal soldier. Dingell even voted for the June 2009 carbon control legislation that Waxman and Pelosi advanced to the House floor, a vote that many felt compounded electoral losses the following year in coal country regions of the South and Midwest.
Democrats still grow emotional over one unity moment. In 1965 Dingell oversaw the House vote approving Medicare, and he kept the gavel the rest of his life. Before the 2010 vote to approve the Affordable Care Act, however, Dingell gave Pelosi his gavel and she led the House Democrats marching into the Capitol with the dean of the House's gavel.
"It was my privilege to hold that same gavel," Pelosi told lawmakers Friday morning.
Old rivals themselves, Pelosi and Hoyer led a tribute to Dingell on the House floor. Hoyer made a last-minute trip to visit Dingell on Wednesday, his second to last day alive, delivering a message from the late lawmaker to his old colleagues: "Our country needs each of us to work together."
One of Pelosi's allies these days is none other than Rep. Debbie Dingell, D-Mich., the wife of the late congressman, who won the race to replace him in 2014. She even gave a nominating speech for Pelosi to remain Democratic leader after the disappointing 2016 elections.
And Democrats who once clashed with John Dingell now realize that their party, in its rush to the future, to the coasts, left behind too many people in the old economy.
"The sadness in the country is that they didn't enjoy that, they didn't enjoy that," Eshoo said, suggesting her party needs to mix the Pelosi approach with some of the Dingell outlook. "Our job is to help to bring about and restore prosperity in different, other regions of the country."
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