No way to know this today, right?
Any pointers to cladestine operations in russia since 1990 available? Those could help to debunk the claims that certain kind of those "cladestine every think is possible" ops are just marketing.
There is a great and current book describing our current posture. Check out "Dirty Wars" for a wonderful intro to our secret wars all over the world. JSOC is operating in many, many countries where we do not have active wars going.
The USA is most definitely capable of undertaking operations in "denied areas."
edit: typo.