President Trump walks into the East Room on Monday to announce his plan to overhaul the air traffic control system. (Jabin Botsford/The Washington Post)

President Trump this week began rolling out what he bills as a massive plan to rebuild America’s highways, bridges, railways and airports — but Sen. Thomas R. Carper (Del.) is nowhere to be seen so far.

Back in January, as one of the Democratic point men on infrastructure, Carper politely asked the new transportation secretary, Elaine Chao, if they could discuss what had been one of Trump’s top priorities from the 2016 presidential campaign.

“It took several months for that to happen,” Carper recalled Monday.

He praised Chao as someone “I like a lot,” blaming her chronically understaffed agency for being incapable of promptly scheduling the meeting. When she told him to speak to Gary Cohn, the president’s chief economic adviser, Carper got one phone call and then participated in an hour-long bipartisan meeting with Cohn a few weeks ago to discuss financing the plan.

“That’s pretty much the extent of it. It’s not the kind of fulsome outreach that one might have hoped for and expected,” said Carper, the top Democrat on the Environment and Public Works Committee.

In a different political orbit, Trump may have marked what the White House is calling “infrastructure week” with a signing ceremony for his first major bipartisan victory: making good on his pledge to drive $1 trillion into rebuilding the nation’s roads, bridges, airports and waterways. Trump regularly won begrudging plaudits from Democrats who saw the plan as something that would energize the economy.

And regardless of the hesitancy of party leaders on Capitol Hill toward big spending, the idea resonated with Republican voters who backed Trump all across the industrial Midwest and handed him the presidency. Those voters heard bridge-building and highway construction, and they saw new jobs for their once-thriving manufacturing regions.

Moreover, in 2015, before they took over leading their respective caucuses, Sen. Charles E. Schumer (D-N.Y.) and Rep. Paul D. Ryan (R-Wis.) were already working on a plan — now shelved — to encourage U.S. corporations to bring home cash stockpiled overseas that could be taxed, with the funds going toward a new infrastructure plan.

In the first days of his presidency, even as anti-Trump activists demanded total resistance, liberal Democrats still craved an infrastructure plan and were willing to cut a deal. “Let me put it this way, if they had been willing to do a real infrastructure package, then I would have been willing to participate,” said Sen. Brian Schatz (D-Hawaii), one of the more liberal members of Minority Leader Schumer’s caucus.

Instead, in coordination with Speaker Ryan and Senate Majority Leader Mitch McConnell (R-Ky.), Trump put the infrastructure plan at the back of the line behind the repeal of the 2010 Affordable Care Act and a complete overhaul of the tax code.

There was an intricate timeline under fast-track procedures for those first two major items, which were expected to pass quickly this year solely with Republican votes, and maybe later this year or early next year Congress would dive into a bipartisan infrastructure plan.

“There was a sense of urgency surrounding Obamacare,” Sen. John Thune (R-S.D.) said Monday, arguing that the health law was in a “death spiral” that had to be addressed. “There was a lot of pressure to fix that right away.”

But it’s not fixed. It’s stuck inside various working groups that McConnell has marched into his office trying to find the right mix. As long as that health-care logjam remains, the move to the tax code rewrite cannot move forward.

That legislative pileup has left the infrastructure plan — arguably the one issue that Trump, who made billions of dollars building things, personally cares deeply about — in political limbo.

So, on Monday, the president began his infrastructure rollout with a proposal to privatize the nation’s air traffic controllers and upgrade the industry’s technology, to be followed by other events in which he will propose a series of tax credits to set up more public-private partnerships to encourage more construction projects.

The push is for $200 billion in federal funding over 10 years, hoping that would spur another $800 billion in private funding for the projects.

Democrats have largely panned this approach as insufficient in federal support and naive in its hopes for private funding. At best, it might lengthen the timeline for projects that were already underway during the Obama administration, such as another tunnel across the Hudson River. At worst, Democrats contend, it will give away tax cuts to private corporations for projects that would have happened anyway.

“This is literally the opposite of an infrastructure package,” said Schatz, a member of the Commerce, Science and Transportation Committee.

Some proposals lack key Republican support. On Monday, Thune, who chairs the commerce panel, and Sen. Jerry Moran (R-Kan.), a senior member of Thune’s committee, reiterated their opposition to the air traffic controller proposal.

Thune acknowledged that Trump’s free-market infrastructure package will probably need to be rewritten because opposition from deficit-hawk conservatives will force Republicans to land solid Democratic support.

“You’d probably have to tweak a bill and the approach a little bit from what the administration is proposing,” he said, calling this week a first “installment” of the plan. “A more traditional, conventional approach to infrastructure, for part of it, I think you could probably get some Democrats.”

But that assumes Democrats even want to help Trump by the time they get to a real infrastructure proposal. His tenure so far has been marked by a stalled legislative agenda, a special counsel investigating his 2016 campaign and constant fights on Twitter that have little to do with day-to-day life in the Capitol.

For now, some Democrats are still talking about their desire to rebuild highways and bridges. If Republicans want to go down that path, someone better call Tom Carper.

“They just don’t have the people, particularly the people who have the ability to reach out to Congress, to develop relationships,” Carper said.

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