Iowa Gov. Terry Branstad last week pledged to work to increase Chinese purchases of American products, particularly agricultural products, if he is confirmed as President Donald Trump’s ambassador to China.

"As governor of Iowa, I saw first-hand the importance of a positive trade relationship between our two countries," Branstad said in his remarks to the U.S. Senate Foreign Relations Committee. "Nearly one out of every two rows of Iowa soybeans is sent to China, as well as $33.5 million in pork in 2016."

The Iowa governor, who must still be approved by the...