In a special edition of Political Wire's podcast, we spoke with three former presidential speechwriters — former Obama speechwriter Jon Favreau, former George W. Bush scribe David Frum, and former Clinton writer Michael Waldman — about the State of the Union address.

They discuss the purpose that the SOTU address serves and how it comes together, and offer some of their expectations and advice on what President Obama might talk about Tuesday in his next SOTU speech.

Here are five takeaways:

1. It takes a long time to write and involves a lot of people: The process of crafting the SOTU isn't so much a traditional writing process as it is an assembly process. It usually starts one or two months in advance, when the president and his team scope out possible themes for the speech. Side by side, policy aides must then determine which policy ideas will fit with the theme and with the speech's limited space. Behind the scenes, federal agencies and officials often jockey to get their favored ideas into the speech, Frum said. Eventually speechwriters and policy aides produce a draft that fits the desired themes and includes the winning policy items. But the process doesn't end there. The draft eventually undergoes dozens of revisions and iterations between the president, his speechwriters, and his advisers.

2. SOTU addresses are just as much about policy agendas as they are about political visions: SOTU speeches often provide laundry lists of specific policy agenda items, a sharp contrast to the sweeping rhetoric and grand visions of inaugural addresses. But given that millions of Americans watch the SOTU address every year, it still provides a highly useful platform for the president to generate political support for his agenda. Although the speeches can run long and pundits deride the laundry lists, "the public is hungry to hear the details of government from the people they elect to lead them," Waldman said. That still holds true, he said, even in today's age of 140-character limits and nonstop political spin.

3. President Obama will likely address economic opportunity and offer reassurances about ObamaCare: The economy has genuinely bounced back since 2008, but the recovery hasn't benefited all Americans equally. In his SOTU, Obama will try to offer hope that this recovery will reach more people, Frum said. It's especially important with the midterm elections at stake. Progressives recently have sought to bring economic inequality to the forefront, viewing that issue as a political winner for Democrats. Expect Obama's speech to reinforce that trend. Said Favreau, "I think he'll be talking about how to expand [economic] opportunity for as many people as possible." Meanwhile, Republicans want to make the 2014 midterms a referendum on ObamaCare. Obama will likely try to reassure Americans that the health care law — whose health insurance exchanges suffered a shaky rollout last year — is working and will keep working in the long run, Frum suggested.

4. Obama should keep Washington's gridlock in mind as he and his team craft his speech: Obama's speech comes as the economy is improving but as Washington, in particular Congress, is as gridlocked and dysfunctional as ever, and as Republicans continually block the president's agenda. Given that political reality, Obama may not have much to lose by going big in the speech. "He should actually talk about what he thinks the country ought to do, and not worry about whether [House Speaker] John Boehner or the Tea Party will go along with it," Waldman said. "I also hope he'll address this broad sense in the country that government is broken, that Washington is dysfunctional, and we're not going to solve the problems if we don't fix the system."

5. Speechwriters don't have as much sway over SOTU as you might think: The idea that a presidential speechwriter serves as the creative genius behind the SOTU address doesn't quite hold water. "It's wrong to think of speechwriters as authors. They're not," Frum said. "They're people who are drafting a portion of a total production, which has many other values than merely the script." And even the speechwriter's "script" undergoes countless changes, whether by White House aides or the president himself. Speechwriters, as a result, can't become too attached to what they write. Said Favreau: "One thing is not to view your own words as sacrosanct. You can't have too much ownership over those. Your job is to channel what the president wants to say."

Listen to the whole conversation here:

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