When he was still the president of the United States, Barack Obama joked about having another job on the side: salesman in chief.

"I'm expecting a gold watch from Boeing at the end of my presidency, because I know that I'm on the list of top salesmen at Boeing," Obama deadpanned in 2013.

Boeing is no ordinary company. It's a pillar of the U.S. economy, both as a military contractor and in civil aviation. It claims to be the country's largest exporter.

But the longstanding special relationship between the U.S. government and Boeing has come under growing scrutiny, particularly after two crashes involving Boeing's 737 Max 8 plane, in 2018 and 2019. Those tragedies prompted significant changes, with a new CEO at Boeing and revamped oversight rules at the Federal Aviation Administration.

Now the latest safety incident involving a Boeing jet, the 737 Max 9, is raising difficult questions about whether that response went far enough.

Investigators are still trying to determine why a panel blew off an Alaska Airlines jet in midair earlier this month. Federal regulators have grounded 171 Max 9 planes with similar configurations, while launching a review of Boeing's manufacturing and production lines.

The head of the FAA says it's time to reexamine the longtime practice of delegating some of the agency's oversight responsibilities to Boeing employees, raising the possibility of moving some of those duties to a third party.

That would be a remarkable shift in how the federal government regulates a company that is an icon of American industry and innovation.

The U.S. helps Boeing sell planes overseas

Boeing's importance to the economy extends far beyond the more than 140,000 people that it employs directly. The company also supports a network of suppliers and contractors that reaches across the country.

"Small businesses are up and down the supply chain," Obama said at the same meeting of the President's Export Council where he joked about earning a gold watch from Boeing. "And when we sell a bunch of airplanes, a lot of small businesses and medium-sized businesses are benefiting from that as well."

Obama isn't the only president to act as a cheerleader for Boeing.

"God bless you, may God bless the United States of America, and God bless Boeing," then-President Donald Trump said during a 2017 visit to a plant in South Carolina where the company builds its 787 Dreamliner.

When it comes to civil aviation, Boeing has no rivals based in the U.S. Its primary competitor, Airbus, is headquartered in Europe, though it does build some planes here.

Still, U.S. leaders are willing to put a finger on the scale in Boeing's favor.

The federal government has an official credit agency, the Export-Import Bank of the United States, that extends financing for overseas buyers. It's sometimes described as "Boeing's bank," because the company is such a big beneficiary.

The U.S. government is, in a literal sense, helping Boeing sell planes overseas — and these days, that largely means the 737 Max series. It is the company's best-selling plane, with thousands of pending orders, and is seen as crucial to Boeing's financial future.

None of this is supposed to affect how regulators at the FAA treat the company. But in the real world, Boeing wields a lot of power and influence in Washington.

"Boeing evidently does think it's too big to fail," Jim Hall, a former chairman of the National Transportation Safety Board, said in a recent interview.

"It's not complicated. In Washington, D.C., as everyone knows, there is a great deal of influence exercised through fundraising to members of Congress," Hall said. "There's a great coziness or familiarity between all of the parties. And so, who's the bad cop?"

737 Max 8 crashes reveal systemic problems

Ties between the U.S. government and Boeing came under intense criticism after the 2018 and 2019 crashes involving the company's 737 Max 8 planes. A total of 346 people were killed.

After the first crash, of a Lion Air jet in Indonesia, Boeing maintained that the pilots were mostly to blame. Five months later, an Ethiopian Airlines plane went down under very similar circumstances.

Regulators in many other countries immediately moved to ground the Boeing Max 8. But the Federal Aviation Administration waited several days, making it one of the last agencies to take that step.

When congressional investigators started digging into what caused the crashes, they found a range of problems at Boeing — both with the design of the Max 8's flight control systems, and with pilot training — and they found insufficient oversight by the FAA.

At a dramatic hearing in October 2019, family members held up photographs of the crash victims while Boeing CEO Dennis Muilenburg testified.

"We can and must do better. We've been challenged and changed by these accidents," Muilenburg told members of Congress.

One of the parents in the hearing room that day was Nadia Milleron, whose daughter Samya Stumo was killed in the second crash. Milleron confronted Boeing's CEO after the hearing.

"I asked him to resign, because I said that he made decisions which killed people, and then he refused to acknowledge it," she told NPR's Morning Edition in an interview at the time.

"Our daughter got on the plane completely trusting," Milleron said. "And she never dreamed that there would be any problem with the plane itself, and there was a huge problem."

Muilenburg was pushed out of his job just a few months later.

"A case study of the complete and total failure of self-regulation"

Congressional hearings on the design and certification of the 737 Max 8 also brought to light some troubling internal emails from Boeing employees, who mocked their colleagues as well as regulators at the FAA.

"This airplane is designed by clowns who in turn are supervised by monkeys," one employee wrote.

Another Boeing employee wrote that a presentation for regulators was "like dogs watching TV," because the regulators didn't understand what they were seeing.

Investigators learned that Boeing had hidden key details about the 737 Max 8's flight control systems from regulators before they signed off on the plane's design.

They also found that FAA regulators had determined after the first crash that the Max 8 was likely to have the same problem again, but did not make those calculations public at the time.

That brought harsh criticism from safety advocates and Democrats on Capitol Hill.

"We must reexamine the current system that allowed for a much too cozy relationship between regulators and companies, including Boeing," then-Sen. Tom Udall, D-N.M., said at a hearing in 2020.

"This continues to be a case study of the complete and total failure of self-regulation," Udall said. "And I think this will go down as one of the big mistakes in history in this area."

A long history of delegating oversight to industry

The FAA has delegated some of its oversight authority to manufacturers since the 1950s. But regulators have come to rely more and more on Boeing over time, as its planes have gotten more complex and supply chains have grown longer.

This pattern accelerated in the early 2000s, says Peter Robison, an investigative reporter for Bloomberg News, and the author of Flying Blind: The 737 MAX Tragedy and the Fall of Boeing.

Regulators at the FAA were pushed by the bosses to hand off more work to Boeing, Robison says — partly because they trusted that Boeing engineers knew the planes best, and partly because it was cheaper for the FAA.

"What I traced was a distortion in the relationship where the regulator came to feel almost that it worked for Boeing," Robison told NPR's Here and Now earlier this month. "The managers worked very closely with Boeing to speed production of planes. And the managers at the FAA really came to treat Boeing as its customer rather than the flying public as the people it was serving."

At the same time, Robison says, the corporate culture at Boeing was changing too, becoming more focused on profit and less on quality.

Max 8 crashes prompt sweeping changes

After the Max 8 tragedies, Congress passed bipartisan legislation aimed at preventing the company or the FAA from repeating the mistakes that led to the deadly crashes. The FAA made changes that were supposed to tighten up how its authority is delegated.

A new CEO took over at Boeing, pledging to restore the company's commitment to quality and safety.

After nearly two years, regulators cleared the Max 8 to begin flying again, and Boeing began trying to rebuild its reputation with airlines and the flying public.

Then came Jan. 5, 2024, when a panel known as a door plug blew off a Boeing jet — this time a 737 Max 9 — at 16,000 feet, raising troubling questions for the company and the FAA once again.

There are several key differences between the Alaska Airlines incident and the Max 8 crashes.

No one was killed or seriously injured last month, although NTSB investigators said the incident could have been much worse had it had occurred at a higher altitude. And while the cause of the latest incident is still under investigation, it appears to be a problem in the manufacturing process, not a design flaw.

Still, Boeing's critics see a troubling similarity between the events. The company once again appears to be putting the bottom line ahead of safety, they say, by rushing planes off the factory floor at the rate of more than one per day.

This time, however, Boeing has moved quickly to own up to its mistake.

"This event can never happen again," CEO Dave Calhoun said at an all-hands meeting last week at a factory near Seattle. He told employees: "We're gonna approach this — No. 1 — acknowledging our mistake. We are gonna approach it with 100% and complete transparency every step of the way."

The reaction of the FAA has been different, too. This time, regulators moved quickly to ground all 737 Max 9 jets with door plugs. And they seem to be in no rush to recertify those planes to fly again.

Another look at how oversight is delegated

The FAA says it's now considering even bigger changes to the way it regulates Boeing.

"It is time to reexamine the delegation of authority and assess any associated safety risks," FAA Administrator Mike Whitaker said last week. "The grounding of the 737-9 and the multiple production-related issues identified in recent years require us to look at every option to reduce risk."

Regulators say they will consider whether to move quality oversight and inspections to an independent third party.

That would be a major shift in the relationship between the FAA and Boeing — one that some safety advocates say is long overdue.

"This is a very smart move by the FAA," said David Soucie, a former FAA safety inspector and the author of the book Why Planes Crash. "The drive for profitability may just be overriding this ability to have an independent delegation within the organization."

It's a difficult moment for the FAA and Whitaker, who took over as administrator just a few months ago. FAA safety inspectors cannot inspect every bolt on every plane that leaves the Boeing factory. But business as usual agency no longer seems like a good option, either.

What's at stake is how the FAA regulates one of the biggest companies in the aviation industry — and in the entire U.S. economy.