Take this outside of basic politics and look at it from a resource management perspective.
There are core professions that need a certain level of staffing and general manpower ( Yes , I said "manpower", some of you activists will just have to live with that ) to generate a functioning civil society.
You need a certain number of soldiers for national defense and general deterrence.
You need a certain number of firefighters, law enforcement, nurses, doctors, truckers, farmers, teachers, sanitation workers, etc, etc to make day to day life actually possible in the United States.
So it's not just SWA and it's not just airlines. You have critical professions that have require a high level of training and many have multiple barriers to general entry. Every police office that resigns in Seattle can't just be replaced in a week. It takes a change over rate of a year or more to get a new officer on the streets and even longer until that person becomes actually functional and possibly competent on the job.
You also have to factor in how functional organizations work. Like NFL teams, you need a certain number of veterans who provide leadership, mentoring and training, while also solidifying the culture in place. So mass turnover creates many long term internal problems as well. No NFL team is going to win anything with a roster wholly full of rookies, even blue chip ones.
There are already critical issues with the current supply chain in America.
First things first, the food supply needs to be secured. People can live without flying and while that impacts many businesses and industries, eventually you can work around most of it. It's unfortunate for those who will truly suffer though or if their segment will be crushed by it. But critically to start, you need stability in people walking into a grocery store and having food be there on a shelf for them.
The other issue is the only truly practical way to galvanized a formerly split society, proven all throughout recorded human history, is to go to war.
No one here wants to live in a society, especially considering the safety of their own children, where going to war is going to be seen as the best cure all for a fractured declining self cannibalizing culture in place.