Transportation Secretary Pete Buttigieg faces one of his biggest tests yet as tens of thousands of outraged Southwest Airlines travelers remain stranded at airports across the country. 

Buttigieg is under pressure to help get travelers home, ensure they are reimbursed for unexpected costs and take steps to prevent this kind of meltdown from happening again.

It’s perhaps the most high-profile moment of the former — and potentially future — presidential candidate’s tenure in the Biden administration. And it presents an opportunity for Buttigieg to take decision action, something critics say has been lacking during his tenure.

“Now, we’ve never seen a situation, at least not on my watch, with this volume of disruptions, so this is going to take an extraordinary level of effort by Southwest. And we will mount an extraordinary effort to make sure that they’re meeting their obligations,” he said on ABC’s “Good Morning America” on Wednesday.

Buttigieg spoke with the CEO of Southwest Airlines on Tuesday, conveying that he expects the airline to “live up to the commitments it has made to passengers, including providing meal vouchers, refunds, and hotel accommodations,” according to a Department of Transportation spokesperson. He also spoke to union leaders that represent Southwest’s flight attendants and pilots.

Southwest has canceled more than 15,000 flights over the holiday period due to rampant scheduling glitches and winter storms, disrupting travel plans for millions of customers. 

“What’s happening this week is just the latest and perhaps the worst manifestation of problems that have been going on since Buttigieg took office,” said William McGee, a former aircraft dispatcher who is a senior fellow at the American Economic Liberties Project.

McGee and other consumer advocates who push for tougher rules on airlines say Buttigieg has failed to crack down on industry practices that have led to widespread consumer complaints. They note that Buttigieg hasn’t levied any fines against large carriers for canceling flights at the last minute or failing to provide refunds.

“We had high hopes for him, and I think, quite frankly, he has been a tremendous disappointment. He could be doing much more, and for whatever reason he has chosen not to use the authority that he clearly has,” McGee said.

Supporters of tougher rules say they would discourage airlines from overbooking flights — a practice that contributed to Southwest’s mass cancellations — and mishandling customers’ luggage. It will be up to Southwest to fix its archaic scheduling system that went haywire over the holidays.

In August, Buttigieg proposed a rule that would require airlines to give refunds if a flight is canceled or significantly delayed. Still, Democrats said it didn’t go far enough, arguing that carriers should also have to pay for secondary costs such as food, lodging and transportation. 

Those lawmakers include Sen. Maria Cantwell (D-Wash.), chair of the Senate Commerce Committee, who said Tuesday that the Southwest meltdown — which has stranded some travelers for several days — shows why the rule needs to be strengthened.

“Consumers deserve strong protections, including an updated consumer refund rule,” Cantwell said in a statement.

Last week, 34 state attorneys general from both parties sent a letter to Buttigieg pushing for tougher airline rules, arguing that the department should impose significant fines for avoidable cancellations and prohibit carriers from selling flights that aren’t adequately staffed. 

Buttigieg isn’t the first Transportation secretary to draw criticism for being too friendly to the airline industry. States have long bemoaned that federal law prevents them from investigating airline customer complaints, citing the department’s futility. 

“Americans are justifiably frustrated that federal government agencies charged with overseeing airline consumer protection are unable or unwilling to hold the airline industry accountable and to swiftly investigate complaints submitted to the US DOT,” attorneys general wrote in a letter to congressional leaders in August pushing them to revoke the law.

Buttigieg’s performance as Transportation secretary is under a microscope in part because he is largely considered to have aspirations beyond the Biden administration. 

Buttigieg’s campaign to be the 2020 Democratic nominee for president gained him national attention and put him on the map as a Democrat to watch for future White House bids. The former Mayor of South Bend, Ind., exceeded expectations and won the Iowa caucuses before bowing out of the race and endorsing Biden. 

Brian Keeter, a former Department of Transportation official under President George W. Bush, predicted that Buttigieg will seek middle ground in his Southwest response.

“The challenge for Secretary Buttigieg is resisting populist demands from some on the left to attack Southwest as a heartless behemoth and call for a heavy-handed regulatory solution with unintended consequences. He’s much too smart for that, and he knows it wouldn’t serve well either the flying public or his political future,” he said. 

Keeter added that he thinks Buttigieg will appropriate this issue “adroitly” and compared it to how he worked with businesses to fix supply chain issues early in the Biden administration. 

“It’s an opportunity for his brand of strategic, collaborative leadership that brings the best minds to the table, strengthens private-public collaboration and gets a long-term win for all involved, especially consumers,” said Keeter, a senior director at public relations consultancy APCO Worldwide.

President Biden on Tuesday said the administration will hold airlines accountable for mass flight cancellations and urged customers who were affected to visit the Department of Transportation’s website to see if they are entitled to compensation.

Biden has previously targeted airlines over so-called junk fees added to the price of tickets. His steps to eliminate junk fees for customers were announced in October as part of his broader efforts to combat inflation.

Republicans, meanwhile, are attempting to pin the blame on Buttigieg for the travel issues.

“Where’s @SecretaryPete? #SouthwestAirlines,” the House Judiciary Committee Republicans wrote on Twitter.

Buttigieg responded, “Good morning! At the moment I’m on Capitol Hill, not far from your offices. We’ll keep getting results for passengers using our authorities & resources as an agency. If you’re calling for policies that would deepen those resources, please be specific – I’d welcome the dialogue.”