From primary stump speeches to, the Trans-Pacific Partnership has garnered a lot of conversation this election season. But many don’t know exactly what it is, or why it matters.Very simply put, the Trans-Pacific Partnership is an agreement which would set new trade and business terms for the U.S. and 11 other countries. If passed into law, it would be the largest regional trade accord in history.Supporters of the TPP say the deal would raise incomes and exports in the U.S.; opponents worry that it will send U.S. jobs overseas and give too much power to corporations. For Justin Sane, singer of the Pittsburgh-based punk band Anti-Flag — which has been touring with the Rock Against the TPP tour — the problems are obvious. When he first heard about the TPP, “what … really grabbed my attention was that this is a so-called free-trade agreement that was negotiated over seven years, in secret, by corporations, lobbyists and lawyers,” he says. “The only people that weren’t allowed in these negotiations were the public and Congress. … And that immediately just sends up a red flag for me.”So when Tom Morello, of Rage Against the Machine, invited Anti-Flag to be a part of Rock Against the TPP, “for us,” Sane says, “it was a no-brainer.” Organized by singer-songwriter and activist Evan Greer, the tour has made stops in the Pacific Northwest, California and Colorado, and Sane says his band jumped at the chance to curate a Pittsburgh show.In addition to Anti-Flag, the free show includes Providence, R.I.-based bilingual dance punks Downtown Boys, Baltimore rapper Son of Nun, and Pittsburgh-based songwriter and labor activist Anne Feeney. “She’s a legend in labor circles,” Sane says. “We really wanted to get her involved because the TPP is attacking labor in a significant way.”Resistance to the TPP is building — former supporters of the deal like Hillary Clinton and Sen. Pat Toomey now oppose it — but Sane stresses that it’s still important for citizens to make their voices heard. “We can bring corporations to a place where they do act in the public interest,” Sane says. “We want a trade deal that is good for everyone.” For more information, visit rockagainstthetpp.org