Sarah Palin is back on Fox! Why is she reappearing now?

Sarah Palin’s back! Back on national TV as a regular, that is. Fox News announced Thursday that they’ve rehired Ms. Palin as a paid contributor. Her (undoubtedly triumphant) reappearance is set for June 17 on the network’s morning show “Fox and Friends.”

“I have great confidence in her and am pleased that she will once again add her commentary to our programming. I hope she continues to speak her mind,” Fox News Chairman and CEO Roger Ailes said in a news release.

The former GOP VP candidate and ex-Alaska governor added that the “power of Fox News is unparalleled” and that she’s “pleased and proud” to be rejoining her old team.

If you recall, Fox and Palin publicly parted ways earlier this year. Fox chose not to renew a contract that had reportedly paid Palin $1 million annually for three years.

She’s probably getting paid a lot less than that now, although terms of the contract weren’t released. Still, there had been some grumbling from Fox about the quality, or perceived lack thereof, of Palin’s on-camera work. So what’s changed? Why have Fox and Miss Wasilla of 1984 chosen to rejoin forces?

Here are our initial theories:

A target-rich environment

When Palin and Mr. Ailes parted ways, President Obama had been comfortably reelected and the GOP was in turmoil. The Republicans are still engaged in reassessment, but for Obama the good feelings of November are but a memory.

GOP members of Congress are continuing to raise questions about the fatal attacks on US buildings in Benghazi, Libya, while IRS targeting of conservative groups is big news. Plus, there’s the new NSA spying-on-Americans scandal on top of the AP subpoena controversy and … so forth and so on.

You get the picture. There are just so many juicy topics for Palin to talk about, it behooves Fox to have her back on. She was a huge hit at the Conservative Political Action Conference this year, proving she’s still got the audience appeal Fox producers crave.

The rise of the competition

Is it a coincidence that Palin’s first reappearance will come on the morning CNN launches its new morning show “New Day”? We think not. Flaunt a celebrity guest – that’s a time-honored TV way of driving down an opponent’s ratings.

And what about the competition that Palin faces herself? Rep. Michelle Bachmann (R) of Minnesota has announced she won’t run for reelection and already appears to be edging in as a new tea party favorite commentator. She was on Glenn Beck’s “TheBlaze TV” show yesterday warning conservatives about the perceived peril of immigration reform.

“We’re losing badly … we need your viewers to melt the phone lines,” Rep. Bachmann told Beck.

Can’t you imagine Palin watching that? “Melting phone lines. … We’ll see who can melt phone lines,” she might say to herself.

Promo platform

In the past, Palin has done well with the written word. Her 2008 “Going Rogue” memoir has sold more than two million copies, and her “America by Heart” was a big bestseller in 2010.

Now she’s got another book on the horizon: “A Happy Holiday IS a Merry Christmas,” scheduled for November release. A platform on Fox would be an invaluable aid in promoting this latest Palin volume, so much so that she’d probably take a lot less money from Fox upfront for her appearances.

Plus, Fox benefits from all the Palin-is-back stories that the scurrilous lame-stream media will indulge in. As the network’s Greta Van Susteren noted yesterday, “it is a free promo for Fox since it will drive her TV critics crazy! They are obsessed with her!