Markets could get difficult to trade moving forward. If the tariff and trade sanction threats weren’t enough, the promises of assistance for farmers coming from the White House and USDA now add another element of political risk for buyers and sellers to navigate. It is indeed hard to keep score of the ongoing stream of political ups and downs that might trigger policy reactions in the coming months before the 2018 election. First, the farm bill has recently become a partisan wedge issue, and its fate is up in the air. A chairman’s mark may be tabled in the House Agriculture Committee as soon as this week, or a one-year extension of the farm bill may just as likely be passed in September before Congress adjourns and heads out to...