Answer: Nixon worked to end "America's longest war"
Explanation:
Even though Nixon's emphasis on his prosperity regarding foreign matters is mentioned in the Washington Post article, there is no mentioning of his labor to end the Vietnam War, which is recognized as "America's longest war". Despite of this, the article includes his words regarding his achievements in the relationship of America with China, the need for peace in mideast, and the goal to destroy nuclear weapons in Russia, among other achievements or objectives.
