Today’s big coffee-war news: McDonald’s will spend $100 million on ads in its bid to Mc up the coffee business. For a lot less money it could figure out how to make good coffee, but evidently it wants to stick to its principles and concentrate on its core competency.

If Mickey D and his mechanical McBaristas succeed in burying Starbucks, it’ll be another dark (and not as in roast) day for Seattle’s economy—a bigger loss than Safeco, almost as big as Washington Mutual. Still, some of those advertising McDollars may come to Seattle; a local agency, DDB Seattle, created McD’s notorious "four bucks is dumb" campaign. So much for local pride.

What can Starbucks do to counter? Today also brought a wild but interesting suggestion for insuring Starbucks’ survival from John Gapper, a columnist at Britain’s Financial Times: become a bank.

This would actually be a good time to start a new kind of retail bank, Gapper argues, because the business is in turmoil and anxious, disillusioned customers are switching banks like crazy.

A Starbucks National Bank would operate online, with only ATMs for physical presence, so it could afford to pay better interest rates. And Starbucks already has 7,000 ready ATM locations distributed throughout the US, plus another 6,000 abroad—more than the megabanks. Think about it: No more desperate searches for invisible ATMs. You can always find a Starbucks.

And there are natural synergies. What better time to sell people $2.45 lattes than when they’re feeling flush after hitting the cash machine? And what better name for a bank than Star bucks?

Just one pitfall: According to boss Howard Schultz, Starbucks is already battling to recover its "soul." These days banks rate even lower on the soulfulness scale than usual. How can an ATM fit into the slow-sipping fireside Third Place Wi-Fi experience?

If anyone has the architects and designers to make ATMs as cozy as scones, it’s Starbucks. And the truly soulless McDonald’s is doing its bit to make Starbucks soulful again. By attacking "Fourbucks" and flooding the world with McCafé, it’s turned yesterday’s big bully into today’s sympathetic underdog.