The last Time Warner deal was the worst deal in history. What is AT&T thinking?

More than 16 years ago, AOL bought Time Warner for $160 billion, in a deal that is now commonly cited as the worst merger in history. Now AT&T wants to buy Time Warner. What the hell is it thinking? The Wall Street Journal thinks the deal could close within days, so we may hear a rationale from AT&T CEO Randall Stephenson shortly. In the meantime, here are some educated guesses about why he thinks the deal is worth doing:

• AT&T doesn’t want to be a dumb pipe — or at least, not just a dumb pipe.
• AT&T knows DirecTV is a shrinking business.
• This deal makes more sense than taking on Google and Facebook
• AT&T isn’t AOL. Neither is Time Warner.