If anyone needed a reminder that Democrats and Republicans still differ on some fundamental issues, it has come with the decision of the Obama administration’s Department of Justice to block the merger of T-Mobile and AT&T.

In a rare but encouraging blow against the sort of business behemoths that anti-trust laws were designed to constrain—especially in areas so critical as communications—Deputy Attorney General James Cole declared: “We believe the combination of AT&T and T-Mobile would result in tens of millions of consumers all across the United States facing higher prices, fewer choices, and lower-quality products for their mobile wireless services.”

“Anyway you look at it, this deal is anti-competitive,” said Deputy Assistant Attorney General Sharis Pozen, who explained that an “exhaustive investigation” by the Justice Department had concluded that removing a low-cost, innovative wireless carrier from a market that is already dominated by two major players would result in less competition and innovation and higher prices for consumers.

Craig Aaron, the president and CEO of the media-reform group Free Press, hailed a moment where “facts and law had trumped politics.” “Blocking this merger is a major victory for the public interest," he said. "The Justice Department clearly based their decision on the facts, and, as Free Press has argued from the start, the overwhelming evidence shows that this merger would lead to higher prices, few choices for consumers, and massive job cuts.

“It’s encouraging to see the federal regulators have not been snowed by AT&T’s promises and bluster. Its smoke-and-mirrors effort was a good front for a while, but when you get down to the facts of the matter, this was a bad idea from the start, and no amount of corporate spin overcome that reality,” added Aaron. But he warned, “AT&T has already invested untold millions in lobbying and campaign contributions, and it is going to play every card in the deck to try to get this merger done.”

AT&T will have an ally who is never going to be accused of putting facts and the law ahead of politics: Texas Governor Rick Perry.

The front-runner for the 2012 GOP presidential nod has positioned himself as a champion of big business—especially when big business wants to get bigger.

Not only has Perry endorsed the AT&T/T-Mobile merger, he has actively promoted it, writing a letter to Federal Communications Commission Chairman Julius Genachowski and the other commissioners, in which he argued that “this merger will continue to provide for great consumer choice, offer a wide range of service options, and spur continued innovation.”

The governor’s letter, sent in his official capacity before he announced his candidacy, urged federal officials to adopt “a light regulatory touch” and “business-friendly policies.”

Perry, who has tried to present himself as a tech-savvy contender (even if he does not quite have the language of Twitter and tweets down), argued in the letter that “the future rests in wireless broadband, and the federal government’s swift approval of the merger between AT&T and T-Mobile would send a strong signal to employers, consumers, and states that our federal government is serious about meeting the communication and technology needs of Texans and all Americans.’

That’s not how the Justice Department or consumer groups see it.

So what’s behind Perry’s different perspective?

Gee, perhaps it is the more than $500,000 that AT&T’s political action committee has given Perry over the past decade.

Watchdog groups accused Perry of engaging in “pay-to-play” politics, which sounds about right.

It was a Republican president, Teddy Roosevelt, who at the start of the last century embraced the trust-busting program of the Progressive Era and taught America that monopolies were bad for consumers, competition and democracy.

Rick Perry is not a Teddy Roosevelt Republican. And, despite his techie pretensions, he is not a 21st-century Republican, or even a twentieth-century one.

Perry’s an old-fashioned nineteenth-century robber-baron Republican. And he’s writing letters to prove it.

(John Nichols, the co-author of The Death and Life of American Journalism (Nation Books), with Robert W. McChesney, is a co-founder of Free Press.)