Canada and Brazil: In 2019, Canada and Brazil reached an agreement on aircraft imports, United States and China: In 2018, the United States and China reached an agreement on steel imports, European Union and China: In 2018, the European Union and China reached an agreement on solar panel imports and Japan and United States: In 2021, Japan and the United States reached an agreement on automobile imports. Why did the two countries in each situation come together for the agreement opposed to one instituting tariffs?