Perot was wrong about free trade. What he was right about was fair trade. They're very different. Fair trade is both a job creator and a quality-of-life improvement for Americans (and the world generally). Unfair trade leads to job loss, though can still lead to improvements in quality of life elsewhere because top-notch, inexpensive goods are still being produced.
Unfair trade includes agreements with nations, China in particular, where the underlying currency itself is distorted; i.e. the yuan. Were the Chinese gov't allow it to continue to strengthen vs. the U.S. dollar, their exports wouldn't be nearly as competitive and U.S. traders would have a stronger hand to play with.