As one of my colleagues recently pointed out at an Extension meeting, both major-party candidates are (at least claiming to be) anti-international-trade. It's true that trade restrictions would be harmful to many segments of the U.S. agriculture sector, including beef. I ran across a great article in Beef Magazine last month that shows the U.S.' top trade partners. The chart below is lifted from the article.
As you can see, Australia is responsible for a substantial proportion of beef (not cattle) imports into the U.S. Our exports go primarily to Asian markets and our geographical neighbors. The article goes into some detail about the recent change in fresh beef imports from Brazil. The new policy is a tariff-rate-quota; details are available in the article and in this video.
Since I strive to tell the other side of the story as fairly as possible, I thought I'd link to what I believe is the most sophisticated argument against the Trans Pacific Partnership I've read. I recommend reading it, even if you are pro-TPP.