Tires: Tire rot safety

Question
I recently purchased a 2002 Nissan Maxima with 17,500 miles, yes it was 17,500 miles.  Tire passed a Maryland Inspection by the selling dealer, but when I took the vehicle to a local Nissan Dealer, they said they should be replaced due to tire rot.  When I inspected the tires you can find small spiderweb like cracking on the side wall near the bead, but other than they they look fine and I have put 3,000 miles on them with no issue.  These are the OEM tires from 2002.  Your thoughts about safety of the tire, am I more at risk for a blow out while driving or should I continue to use them an keep an eye on them.

Your opinion is greatly appreciated

Answer
Mike,

Recent bulletins from the tire manufacturers indicated that tires degrade due to time and while there is some variation in the limit, certainly a 14 year old tire is well beyond it.

Cracking is an indication of the state of the rubber and while a little cracking is to be expected, lack of cracking is not an indicator that things are fine.

I think the risk is too high to try to save a few bucks on tires.  I'd replace them.