They do but from past experience it’s a big fight to get them to pay fair value. I posted this on a fishing forum I’m on and they suggested homeowners insurance would usually cover it. I still have to look at my policy but seemed like a good thoughthttps://www.transportation.gov/lost-delayed-or-damaged-baggage
Certainly, I'd check with the airline, but it reads they are liable for up to $3,800, per passenger.
Limits on Baggage Liability
Domestic Baggage Liability
Edit,
- For DOMESTIC flights, DOT regulation allows airlines to limit their liability for a lost, damaged, or delayed bag. Airlines are free to pay more than the limit, but are not required to do so.
- The maximum liability amount allowed by the regulation is $3,800 per passenger.
For proof, you could photograph the contents of your bags, with the itinerary, before leaving home.