Will Obama call for political civility in Tucson speech?

President Obama, who has for years bemoaned incivility in politics, must decide Wednesday whether his speech in Tucson is the right time to repeat that message

The White House announced last night that the president will appear at the University of Arizona at an event the school has dubbed "Together We Thrive: Tucson and America." He is likely to make his longest formal remarks since the shooting in Tucson that killed six and injured 14 others, including Rep. Gabrielle Giffords (D-Ariz.).

So far, President Obama has not joined the Democrats who have argued the shooting was a manifestation of a tense political climate that is largely the fault of Republicans. Obama's comments have been brief and completely non-controversial, such as on Monday, when he praised the people who wrestled the shooter down to the ground.

Republicans have criticized the focus of liberals and the news media on partisan rancor, arguing that it is wrong to implicitly link the tea party and conservatives to the alleged shooter even as little evidence has emerged he had any particular political motive. Some in the GOP have even praised Obama for his measured tone.

Will that change on Wednesday? White House aides have not yet said whether the president will simply honor the victims and their families or speak more broadly about the tragedy.

If they want to use the speech to urge greater civility in politics, White House aides won't have to look very hard for language. Obama's speeches in his 2008 presidential campaign were as much about changing the tone in Washington as shifting its policies to the left.

In his State of the Union address last year , Obama said, "some of the unity we felt after 9/11 has dissipated."

"We can argue all we want about who's to blame for this, but I am not interested in re-litigating the past," Obama continued. "I know that all of us love this country. All of us are committed to its defense. So let's put aside the schoolyard taunts about who is tough. ... Let's leave behind the fear and division, and do what it takes to defend our nation and forge a more hopeful future - for America and the world."

But if Obama uses such language on Wednesday, it might not unify the country. The comments of Democrats, such as Obama ally Sen. Richard Durbin(D-Ill.), who on Sunday invoked several comments by Sarah Palin in discussing the shooting, have made many Republicans wary of the Democrats' motives in speaking of increased civility.