Republican Sens. Mike Lee (Utah), left, and Rand Paul (Ky.) are threatening to vote against the GOP’s emerging House bill to repeal the Affordable Care Act. They object to a proposed tax credit it contains. (J. Scott Applewhite/Associated Press)

The last time a Republican president and Republican Congress passed a tax cut, in 2003, Peter J. Roskam was serving in the Illinois state Senate.

The last time a Republican president and Republican Congress overhauled federal health policy, also in 2003, when prescription drug coverage was added to Medicare, Michael C. Burgess was serving his first year in the House.

Flash forward 14 years, and now those two lawmakers, Reps. Roskam (R-Ill.) and Burgess (R-Tex.), are senior members of the influential committees trying to overhaul tax and health policy with a new Republican president and a GOP-controlled Congress.

Across the Capitol, there’s a new generation of Republicans who have risen to power since the GOP last attempted to enact a sweeping agenda that would overhaul big pieces of the economy such as the health-care and tax systems. Quite simply, there aren’t many Republicans around with muscle memory of what it’s like to craft large pieces of legislation that rely almost entirely on votes from their side of the aisle.

The problem is particularly acute in the House, where just 60 Republicans — a quarter of their caucus — have ever served in the majority with a GOP president.

Moreover, more than 160 House Republicans are getting their first taste of working with a Republican president. Their entire legislative careers until now have been dedicated to stopping an administration’s actions.

Some GOP elder statesmen are worried this block-everything mentality is still the mind-set dominating several dozen Republicans.

“They’ve got to get in line,” Trent Lott (R-Miss.), a former Senate majority leader, said in an interview. The former senator said some conservatives who are threatening to hold up the emerging health and tax bills do not understand the difference between controlling Congress alone and having both Congress and the White House.

“[The GOP leadership is] going to have to be prepared to crush that,” he said.

It’s not just a problem in the House. Over in the Senate, a trio of next-generation Republicans — Ted Cruz (Tex.), Mike Lee (Utah) and Rand Paul (Ky.) — are threatening to block the emerging House bill to repeal the Affordable Care Act. They don’t like a proposed tax credit it contains, viewing it as a new entitlement.

The trick for House Speaker Paul D. Ryan (R-Wis.) and Senate Majority Leader Mitch McConnell (R-Ky.) is to convince these younger Republicans that while they might not get everything they want in the big health-care and tax overhauls, they have been handed a golden opportunity to pass what is by all measures a very conservative agenda. GOP aides noted they wouldn’t be averse to a tweet from President Trump backing the Hill leadership’s agenda.

Both Republican leaders want to pass a health-care overhaul in early April before Congress leaves town on a two-week spring break.

There is an example from 2001 of how things could work, Lott recalled, pointing to George W. Bush’s first year in office, when the Senate was split 50-50 and the majority hinged on Vice President Richard B. Cheney’s tiebreaking vote.

Republicans had agreed to a massive $1.3 trillion tax cut, but moderate Senate Republicans demanded more funds for special education. House conservatives opposed the additional money, but that was the price they had to pay to get the bigger issue to Bush’s desk for his signature.

“We managed to make it work,” Lott said.

Today’s Senate does have several seasoned hands involved in the current legislative fights, particularly Sen. Lamar Alexander (R-Tenn.), a former governor and proven dealmaker. In addition, Sen. Orrin G. Hatch (R-Utah) has been in office more than 40 years and is now chairing his third panel, the Finance Committee, with oversight of health and tax matters.

But in the House, Reps. Kevin Brady (R-Tex.) and Greg Walden (R-Ore.) have a combined total of 18 months respectively chairing the Ways and Means and Energy and Commerce committees. They are in charge of writing the House versions of the tax and health bills.

Roskam is chairman of the tax subcommittee at Ways and Means, and Burgess chairs the health subcommittee at Energy and Commerce. Both are in their first year running those key policy venues.

Sen. Patty Murray (D-Wash.), the most prolific Democratic legislator of the last five years, wonders whether any House Republican beyond Ryan has the stature to make the deals.

“It doesn’t just happen because you decide to write something on a wall and put it on a piece of paper,” Murray said. “It’s called catching the car if you’re the dog. Saying something as a campaign slogan is easy.”

In 2013 Murray and Ryan, then the chairmen of the Senate and House budget committees, crafted a compromise federal-spending outline that virtually guaranteed no government-shutdown standoffs for two years. The easy part, Murray said, was drawing up the policy. Then they had to sell it.

“It wasn’t just going in a room and write it,” she said. “We had to actually go and talk to people, work it, make sure we had the votes from each side. It was a lot of work.”

Even when Republicans have the most experienced legislators, getting big things done can still be difficult. Back in 2003, Rep. Bill Thomas (R-Calif.), a 25-year veteran at the time, chaired the Ways and Means Committee and had to fight, scrap and claw the Medicare bill to final passage.

The vote, beginning about 3 a.m. in late November, was held open nearly three hours before the last holdouts came around, for a final vote total of 220 to 215.

There were 25 Republicans who bucked their leaders and the White House, including a second-term congressman from Indiana, Mike Pence. The legislation only passed because 16 Democrats voted with Thomas.

Today, Ryan — who voted for the 2003 bill — is not expecting a single vote from the Democrats to repeal the ACA. If 25 Republicans take the route that Pence, the future vice president, took in 2003, the legislation will fail.

Trump’s administration is now stocked with four House Republicans, leaving Ryan just 21 votes to spare from his side to still win in a close vote. McConnell can spare just two votes in the Senate, or else the ACA overhaul fails there.

No one is certain whether this GOP generation is ready to follow its leaders.

“We’re fixin’ to find out,” Lott said.

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