Answer:
The Mexican War
Explanation:
Mexican-American War, also called Mexican War, Spanish Guerra de 1847 or Guerra de Estados Unidos a Mexico war between the United States and Mexico (April 1846–February 1848)
It is being used as an adjective in the sentence, so the definition is,
<span>"(of an action) convenient and practical, although possibly improper or immoral."
</span>
The meaning of the word "expedient" most likely means practical or convenient
Answer:
"Take it away," he said, "because I have no use for it."