No, the U.S Media did not cause the loss of the war because the American strategy from the start would have inevitably caused the loss of the war anyway; the U.S media just helped to speed up that defeat.

The Vietnam War was the first televised war. According to the now retired Lt. Gen. Phillip B. Davidson "The war was literally piped into the living room, bedroom, and kitchen of most Americans”. Furthermore the former U.S. Commander in South Vietnam, General William C. Westmoreland noted that Modern technology "provided the press a means of indirectly involving the American public with the war on an almost hourly basis."
Despite initially positive media coverage of the war, it soon became increasingly negative, in some cases falsely so. It has been suggested that the media coverage of the Tet Offensive was an exaggeration of the true course of events that helped shock the American Public. But did the media coverage of this major battle really change public perception leading to America withdrawing from the Vietnam War?

With the outbreak of the Tet Offensive the Vietnam War had hit the urban areas and had subsequently become more reported on than at any other point previous in the war. Many of the Journalists had not experienced war at first hand to such a scale and were shocked by what they were seeing and the ferocity of the attacks. The surprise nature of the attack coupled with the warfare inexperience of many journalists present in Vietnam saw many of them change their verdict on this war in Vietnam. They no longer accepted the official reports of progress from government and military announcements. The Tet offensive seemed to show that America was not winning the war against the communists in the North and so subsequently the media coverage reflected this.

The most famous report on the Tet offensive was by CBS News reporter Walter Cronkite. In a