I am pretty sure that I read that obama had mandated his banking zar to require chipped cards in 2015. I believe that to be so.
A lot of you guys are mixing everything up.
The mandate in 2015 is for banks/credit card issuers, to include the chip technology (not necessarily contactless) on the cards. There is no mandate on the merchants to update their terminals for that; merchants can keep using the magnetic stripe, but they will now have to pay for the cost of the fraud (instead of the bank).
Now regarding NFC vs Apple Pay. Apple Pay requires NFC to work, but NFC doesn't mean Apple Pay will work; Apple Pay has both technical and contractual aspects to it. Technically, most NFC terminals should be able to handle Apple Pay, but for multiple reasons large retailers like Walmart, which control a lot more of their payment process than small shops can opt out of Apple Pay if this goes against their interest.
For small shops, then NFC support is usually equal to Apple Pay support, as there would be no benefit for them to opt out.
Finally, remember that Apple Pay is a wallet; and if the card you stored is not a type of card usually accepted by the merchant, using Apple Pay won't magically make it work.