Normally for a 3 Word .US to have any significant value it needs to be a highly searched term.
The US market is not the easiest to understand. What is in demand are
1.) 1 Word Generics. If it is connected to a product or service that is even better.
2.) High search volume terms with a clear use.
3.) GEO domains
I have to say watching .US drops daily this is mid $XX max, unless you find an end user which is possible.
Brad