Less than 48 hours from now, Chicago Public Schools teachers promise they'll be on a one-day strike.

Along with Chicago State University students whose education is being stolen from them, fast-food restaurant workers who want McDonald's to pay at least $15 an hour and other offended groups, they'll rally, march, make your evening commute interesting and otherwise protest what the Chicago Teachers' Union terms Gov. Bruce Rauner's "failed fiscal policies."

I'm sympathetic to much of that — especially the increasingly dire impact Springfield's budget standoff is having on students and their schools, social-services recipients and other groups who tend not to vote Republican. This budget impasse is a public disgrace.

But the CTU is fooling itself if it thinks marching around City Hall is going to move the needle 200 miles south at the Statehouse. And it's wrong if it thinks that Rauner and his unwillingness to raise taxes as high as the union wants are the only obstacles to success.

The truth is that the April 1 "Day of Action" is at least as much about internal CTU politics as it is about carving out a path to success—and that's no joke.

Though CTU has strived mightily to extend the upcoming protest into a sort of mini-general strike, the action is a reaction to the stalled negotiations with CPS.

The union is playing defense in the current round of talks, attempting to protect things such as annual "step-and-lane" pay hikes and the fact that workers now pay only 2 percent of salary toward their generous pensions. Unions don't like playing defense—especially a union led by Karen Lewis. But the fact is, “>CPS is effectively broke , its debt so much junk. The only true exit route runs through Springfield.

Now Lewis, however much she adopts the stance of a provocateur, is smart enough to know that the CPS' options now are limited. That's why she and her leadership crew agreed several weeks ago to major concessions, particularly on the pension side, as part of a new contract.

But Lewis' members aren't as smart. Presented with the deal she negotiated, they revolted. The CTU's expanded bargaining committee unanimously rejected the package, sending a message to Lewis that, if she wants to be re-elected as president in late May, something will have to change.

Voila, the upcoming Day of Action. A bit of red meat for the CTU's militant wing.

CTU Vice President Jessie Sharkey disagrees. He terms such a theory "wrong." If the idea was to shore up Lewis' militant credentials, the union would walk for real on May 20—a few days before the CTU elections—when even CPS agrees that a contact strike would be legal, Sharkey said.

No, Sharkey told me, the day of big action has been launched because, "We think protest works."

Directly or indirectly, it will pressure Rauner and lawmakers to boost taxes and hike aid to CPS, he said. "It's a way to show the people who have the power to pick up the phone and call Rauner."

Somehow, I don't see Rauner and the Republicans caving. But how about Downstate and suburban Democrats who are leery of seeming to go out on a limb to bail out Chicago schools? Will a big display of force influence them?

"I understand the union's frustrations," said one of those lawmakers, McHenry County Democratic Rep. Jack Franks. "It's their right (to strike). I just don't think it's going to be swaying many people."

If CTU really wants to change minds, instead of marching in Chicago they ought to "be in Springfield talking to people."

The protest will help spotlight the reality that Illinois' system of funding grade and high schools is broken everywhere, says Sen. Andy Manar, D-Bunker Hill, a leader of efforts to revamp and better fund the formula.

But will a one-day strike in Chicago help accomplish that? "I don't know," replied Manar, who went on to talk about how one school system in his district is so short of cash that it's laying off 40 percent of its staff.

If CTU really wanted to lean on someone, perhaps it could stop by the office of House Speaker Michael Madigan.

Other leaders, including Senate President John Cullerton, a Democrat, have a state pension-reform plan they'd like to move, a plan that Rauner has said he could support. But Cullerton hasn't moved it because the plan has problems in Madigan's House.

And, of course, the near unanimous word out of Springfield is that Madigan is "playing a long game" and won't seriously negotiate on any budget deal until after the November general elections—by which time CPS may be officially broke.

I hope the teachers and their allies have a good time walking around and looking tough on Friday. Like I said, I'm no big fan of Rauner's governance. But if they think these protests will do anything except deprive Junior of a day in school, make them feel good and maybe help Karen Lewis get re-elected, I have a bridge to sell them.

Bring umbrellas, folks. The weather forecast calls for rain, maybe mixed with a bit of snow.