MAGA world is melting down after yet another star pulled out of the Great American State Fair, a Trump-backed celebration commemorating America’s 250th birthday.Scheduled to take place on the National Mall from June 25 to July 10, the event was slated to include nine performers, organizers announced on Wednesday. But, within two days, most of the acts had publicly distanced themselves.“I was presented with an opportunity to perform at a nonpartisan event but that turned out to be misleading,” Grammy-nominated vocalist Martina McBride wrote on X on Thursday.“Things started changing and what we were told is, in fact, not what is happening,” the “Independence Day” singer added. Her post went viral, garnering more than 3 million views — and provoking sour grapes from some Trump supporters.Martina McBride’s withdrawal from a Trump-backed concert on the National Mall has triggered a MAGA meltdown (Getty)Richard Grenell, Trump’s envoy for special missions, grumbled on X: “You’ve always been a woke Lefty.”“The Intolerance is coming from your side,” Grennell, who formerly helped lead the Trump-Kennedy Center, wrote in a later post. “Why can’t you people be around people that disagree with you politically?”Others in MAGA world quickly dug up footage showing McBride performing for Democrats — including former President Barack Obama — decrying what they saw as blatant hypocrisy.“You sang for Obama, but not for 250 America,” one user with a profile picture of Trump wrote. “Thank you for showing us your true face.”“Was a big fan, so disappointing you don't care about at least half of you audience,” another chimed in.In addition to McBride, five other artists have bowed out of the concert series, including funk group The Commodores, rapper Young MC, pop duo Milli Vanilli and singers Morris Day and Bret Michaels.Only three acts currently remain: Vanilla Ice, C+C Music Factory and Flo Rida.Freedom 250 is the public-private partnership organizing the event. It was established by President Donald Trump to help spearhead yearlong celebrations of the country’s semiquincentennial.