Is the US postal service responsible for mail they admit to destroying, like an envelope?

I received a letter from the postal service saying that they mistakenly ripped an envelope that I sent thru the mail. They sent me a torn end of an envelope that I know had a money order with it but no money order or billing paper was sent back. Is the post office responsible for this?Is the US postal service responsible for mail they admit to destroying, like an envelope?
Money Orders are traceable. They can only be cashed by the party it is made out to and you should have the carbon copy. I do believe they are called Integration Systems. Is the US postal service responsible for mail they admit to destroying, like an envelope?
not unless the sender paid extra for insurance.