"It doesn't matter what scale, as long as you have an opinion and can back it up," he said.
Rainer says his job is to explain the news to his fans.
"With this war, it is important to get kids on the right track," said Rainer, who maintains an online journal with daily updates on the band's official Web site (www.rivercityrebels.com).
"It is important to be informed, but it is hard with the way media portray things," he said.
Many of Rainer's posts contain links to articles about the war.
And for the most part, Rainer and the band have received positive reactions. But Rainer also welcomes other opinions, as long as they are intelligent.
"I like second-guessing, as long as it can be backed up," Rainer said.
"I don't like ignorant people who say, 'Nuke it all,' " he said.
As for live shows, the band tries to play more than talk.
"There is a fine line between having an opinion and preaching," said Rainer, who tries to avoid that at all costs. "But if something needs mentioning, we'll mention it."
The band is touring in support of its fall 2002 release No Good,No Time, No Pride. The album is its third and finds a middle ground between the first two. Its debut album, Racism, Religion, and War, was highly political, while its sophomore release, Playin' to Live, Livin' to Play, featured more personal content, Rainer said.
The Rebels are good friends with headliner Catch 22, whose trumpeter is the Rebel's booking agent, and fellow opener Madcap, who they played with two years ago on the Vans Warped Tour.
Madcap is a punk band with a sound similar to the punk revival bands of the '90s. And like their tour mates, politics is one of the topics touched upon in their songs.
"If we do [talk about politics], it's never straight-out preaching," said lead singer and guitarist Johnny Madcap. "We try and put it in a story."
Madcap believes the current war is a shady situation and says the band does not agree with President Bush.
But Madcap does agree with the Rebels on the way media outlets are covering the war in Iraq.
"No one knows what's going on," Madcap said.
"And we're not going to put it in a song if we don't know," he said.
Rainer said he takes pride in the band's ability to guide people to information.
"It's hard seeing people confused in their daily lives," he said. "People should have integrity to stand up against what's going on. It's patriotic to stand up for what you believe in."
Doors open at 8 p.m. and tickets are $12.