On Monday at the Mobile World Congress in Barcelona, Spain, 24 of the world's best-known telecom carriers tacitly declared Apple (NASDAQ:AAPL) their mortal enemy.

The group is known as the Wholesale Applications Community (WAC) and its members include China Mobile (NYSE:CHL), NTT DoCoMo (NYSE:DCM), and U.S. heavyweights Verizon (NYSE:VZ) and Sprint Nextel (NYSE:S). It proposes to create a new "applications ecosystem" for developers to market software that will function on any handset or network.

It's a laudable idea. Google's (NASDAQ:GOOG) Android endured criticism when some software built for the OS failed to operate on supposedly compatible Android handsets. Preventing this problem from occurring elsewhere is smart business.

But there's more than compatibility at work here; this is also the embattled telecom industry's do-or-die response to Apple's App Store. Carriers know that developers have become the new kingmakers of their world. They also know that AT&T (NYSE:T) has been one of the coders' few beneficiaries, thanks to the iPhone.

So, in that respect, the WAC makes sense. Here's what doesn't: AT&T joining the movement. Yeah, that's right. The former Ma Bell is listed among the consortium's founding double dozen.

Et tu, T?

When asked to comment on the company's plans for the consortium, an AT&T representative declined comment beyond what was in Monday's press release. Fair enough, but Apple can't be happy about this -- unless, that is, plans are already underway to have a Verizon or T-Mobile iPhone here in the U.S.

Is a new iPhone already in development? Share your thoughts in the comments box below.

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Fool contributor Tim Beyers is a member of the market-beating Rule Breakers stock-picking team. He had stock and options positions in Apple and a stock position in Google at the time of publication. Check out Tim's portfolio holdings and Foolish writings, or connect with him on Twitter as @milehighfool. The Motley Fool owns shares of China Mobile and is also on Twitter as @TheMotleyFool. The Fool's disclosure policy is up all night.