Final answer:
The Vietnam War influenced American public policy significantly, leading to the passage of the 26th Amendment, lowering the voting age to 18, and the 1973 War Powers Resolution, aimed at restricting presidential military autonomy.
Step-by-step explanation:
The impact of the Vietnam War on American public policy is reflected in several developments, but two notable examples are the passage of the 26th Amendment and the shift in presidential war powers as a result of the War Powers Resolution.
The 26th Amendment, ratified in 1971, lowered the voting age nationwide to 18 years. This was a direct response to the draft and the argument that if 18-year-olds could be conscripted to fight for their country, they should also have the right to vote. The Vietnam War's draft system had brought widespread protest and debate about the voting age.
Presidential war powers were significantly affected by the Vietnam War as well. The breaking news of secret bombings and the publication of the Pentagon Papers led to public distrust towards the executive branch's conduct of foreign policy. This culminated in the War Powers Resolution of 1973, which aimed to check the president's power to commit the United States to an armed conflict without the consent of Congress, a clear shift from the previously more autonomous presidential military decisions.