One of our crops is soybeans. China loves US soybeans. (https://www.agweb.com/article/will-chinas-hunger-for-us-soyb...) US soybean exports are one of the obvious targets of any trade war with China. Artificially reduced demand (due to what is in effect a, um, regulation) doesn't seem like really good news if you grow soybeans, right?
The consensus in the media is that it is actually the manufacturing / resource / agriculture states (eg: the "red states") who will be hurt the most by tariffs (eg, articles like this: http://money.cnn.com/2018/03/05/news/economy/trade-war-red-s...). Professional opinion wise, I searched and actually couldn't find an economist who had anything positive to say about tariffs (if someone can find one, I'd love to read the link, but it's pretty telling that the overall sentiment is that negative). So right now, I'm not sure at the moment what long-term benefits you are thinking of. Political or strategic, maybe?