Leslie Berland has a curious job. She’s paid to think about all the ways to make her company’s flagship product obsolete.

Berland leads digital partnerships and development at American Express, the company that pioneered the notion that a piece of colored plastic could not only buy stuff but raise your social status. In the future that Berland anticipates, a black card or a gold card won’t mean any more than a purple card, because you won’t have a card at all. Even American Express believes the plastic in our wallets eventually will go away.

At a recent event, hosted by Andreessen-Horowitz, on the future of retail, Berland pointed out that there are two things you always have with you: a credit card and a smartphone. The day is coming when we combine them. “What we are hyper-focused on is how do we merge those two things,” she says. “Especially as one day the physical card will disappear.”

Berland is not alone in thinking plastic is on its way out. Figuring out how to make smartphones the primary way we pay for things is one of Silicon Valley’s great white whales. The same minds that have put airline boarding passes on our phones alongside every song ever recorded and video calling a la The Jetsons are trying to crack this problem. Everyone from Google and Apple to Square is pondering this.

So far they’ve had little success. But, ironically, this creates an opportunity for the very industry these tech giants are trying to disrupt. A company like American Express has every reason to want things to stay as they are. But if it’s willing to concede its core product’s days are numbered, it has a chance of beating the Apples and Googles of the world in the race to redefine payment tech. That’s because it’s got a key advantage over Silicon Valley: Amex already is in people’s wallets.

There are countless apps that already turn your phone into a credit card substitute: Google Wallet, PayPal, Venmo, LevelUp, Coin, Loop, and others abound, not to mention retailer-specific offerings like the Starbucks app. But with so many offerings, the offline merchants who still account for the vast majority of U.S. retail spending are reluctant to gamble on any one of them as the emerging standard. This hesitation creates a self-fulfilling loop in which consumers won’t commit to an app because they don’t know which stores use it. In the meantime, everyone just keeps swiping their cards.

As Berland describes it, this puts American Express and other major credit card companies in a unique position to make mobile payments happen. For them, the “point-of-sale gap” already is bridged.

The various smartphone apps act as credit and debit card aggregators—skins for what you already have in your wallet. That makes these companies what Berland calls “frenemies” to companies like Amex. They encourage use, but they stand between card companies and their customers—a concern for American Express especially, since, unlike MasterCard or Visa, it doesn’t use banks as intermediaries. Amex’s business depends on its customers embracing the concept of “membership,” which the company reinforces through loyalty programs and other perks. These have the potential to get diluted when a different company’s app stands in between Amex and its members. Also, those third parties get a piece of the customer data so valuable to AmEx.

Ultimately, Berland believes the key to getting mobile payments to catch on won’t be the technology but the experience it enables. Amex, Berland says, knows about its customers: what they buy, where they are, how they spend their money and time. Used the right way, she says, that data can be leveraged to make shopping more convenient and more fun. She acknowledges the danger of coming across as Big Brother. But she claims the company’s own focus-group research has found this doesn’t bother customers.