The cliche: Rick Perry has become the latest candidate to embrace simplicity as a first principle, by proposing a flat-tax that is measured by its tax form rather than its policy merits. It's also part of the idea that he's borrowing from the 1996 and 2000 presidential candidate Steve Forbes. Perry put forward his proposal for a flat-tax today in a Wall Street Journal op-ed, writing, "This simple 20 percent flat tax will allow Americans to file their taxes on a postcard." He borrowed the "postcard" line from Forbes, who often touted it in his stump speeches and writings while running on a platform mainly staked to his own proposed flat-tax. Reporters today seemed to really like the enduring "postcard" imagery, featuring it prominently in their news reports about the tax plan  Washington Post blogger Jonathan Bernstein, National Journal reporters Alex Roarty and Rebecca Kaplan, the Los Angeles Times, and Bloomberg, too, all prominently mentioned the postcard or used Perry's line from the op-ed as their leading quotes.

Why it's catching on: A decent question, and one put forth by Washington Post reporter Jia Yin Lang, who points out:

History shows that those who propose the flat tax while running for president -- a group that includes publisher Steve Forbes, Sen. Phil Gramm (R-Tex.) and California Gov. Jerry Brown (D) -- tend to flame out.

So why would Perry join the fray and link back not just to the policy but to the very language of someone who had such a spectacular failure of a presidential campaign? Well, as Jonathan Chait points out in Daily Intel and Lang herself also notes, it's the whole raising taxes on the poor and middle class aspect of flat taxes that makes it unpalatable, and actually, the simplicity of filling out taxes on a much smaller tax form seems to be what has kept the flat-tax proposal around for all these years. Thus did Herman Cain highlight the main advantage of a flat-tax -- its simplicity -- with a catchy "9-9-9" slogan. Perry's campaign is doing the same, handing around an (enormous) "postcard" tax form to show voters just how awesome it would be to pay his flat tax rate. Cain, Perry, and Forbes seem to be looking for the voters who so yearn for the day when they can fill out taxes in the easiest way possible that in fact, they don't think about how much they'll pay or how the government will spend their tax dollars.

Why else? Perhaps too Perry is appealing not just to those voters who value simplicity over everything, but the conservative base that values a quainter time. There's a reason none of these flat-tax proponents are advocating a tax form that could be filled out simply over the web. (Logistics question: how does one include a personal check in an envelope-free postcard?) It appeals to the simpler times when everything you had to say from your European vacation could be said on pretty piece of card stock.