In 2004, Michael Franti visited Baghdad, the West Bank, and the Gaza Strip to see how ordinary people were making out amidst armed conflict. The result was a feature-length documentary (I Know I’m Not Alone) and this fervently uplifting album. Having long ago outgrown his roots in ’80s hip hop and funk to embrace reggae, mainstream rock, and sunny, soul-flecked pop, Franti can croon sweetly, Bob Marley-style, or deliver a gruff lecture with equal ease. Despite some eloquent diatribes against the evils of militarism, he shuns hateful impulses, prescribing tolerance and old-fashioned love as the antidotes to strife. “God is too big for just one religion,” Franti growls to a pumping beat, later murmuring, “Don’t let your mind be so darn judgmental.” And the title song of his film borrows a page from the U2 playbook, hitching its positive message to a shimmering anthem. Yell Fire! performs a miracle, making optimism seem not foolish but downright necessary.