Answer:
The statement shows that many of the American men died (sacrificed their lives in Vietnam) in order to fight for their country's cause. A cause (national unity with other countries through imperialistic means) that people blindly followed and it didn't care whether many people died just so it can prove its pride.
Explanation:
The question above is related to the "Senate Committee on Foreign Relations" that occurred in 1971. John F. Kerry made a speech on behalf of the veterans who testified the war crimes that happened in Southeast Asia.
The war was meant to colonize the Asian countries due to the expansion of the United States since the countries resisted. Many of the countries resisted because they didn't want the idea of foreign policy for they wanted to be liberated from the colonizers.
So, this explains the answer.