The Vietnam war was viewed as a pointless war, just taking lives for no reason. The media focused mainly on the failures of the war, as opposed to the positives. This was turned to be LBJ's fault, and the public wasn't happy.
The United States wasn't defeated on the battlefield, but had lost its first war. More than 58,000 Americans were killed and more than 300,000 wounded. The United States spent about $140 billion on the war.
This was the longest and the bloodiest of the Tet Offensive Battles. (The turning point of the war). The Viet Cong was prepping for the attack a couple days before. Their plan was trying to gain control over Hue, and other parts including all of Gia Hoi, and the southern half of the Citadel. They succeeded.
This was the turning point of the Vietnam War. Democratic Republic of Vietnam came to Hanoi for the funeral of Senior General Nguyen Chi Thanh. Here, they discussed an efficient way to quickly end the Vietnam war. The biggest loser from this situation was the Viet Cong. They lost most of their communist allies.
The two phase US military operation attack against the Iron Triangle. The target of this attack was the headquarters of the VC Military Region IV and its allies.
Both the Truman Doctrine and the Eisenhour Doctrine state that the United States will add assistance to any country actively resisting Communism. If any threats or attacks are made from a Communist country on a capitalist, the United States will see this as a threat on them, and intervene. This will cause a outbreak between the countries.