Why did the British press in Vietnam operate under fewer constraints than their US counterparts?

There are multiple reasons the British press was treated differently than that of the United States with respect to reporting from Vietnam. First, the British prime minister during the period of greatest escalation in American involvement in Vietnam as Harold Wilson, leader of his country’s liberal Labor Party. While US President Lyndon Johnson was similarly liberal, Johnson was overseeing the American role in Vietnam, and Wilson and his party’s opposition to the war in Vietnam superseded what otherwise would have been a more cordial relationship. Unlike France, the former colonial power in Vietnam (and Laos and Cambodia), Britain did not have an interest in the conflict that had ensnared the United States. The British government’s antipathy towards the American role in Vietnam, then, allowed for far greater freedom on the part of British newspapers and television and radio broadcasters (i.e., the government-owned British Broadcasting Corporation, the BBC, which enjoyed a monopoly on television broadcasting during the Vietnam War years and reflected that government control).
Another reason for the greater latitude enjoyed by the British press operating in and around Vietnam was the fact that it was British and not American. While the US military imposed restrictions on American reporting—restrictions that were increasingly ineffective as the war progressed—it was difficult if not impossible to control the British. Britain was not a party to the conflict and, as noted, its government was not particularly friendly to the US role in Vietnam. Restraints on reporting from British journalists, then, were minimal.
Fierce opposition to the war among Britain's liberals further helped to buffer the British press from whatever efforts might otherwise have been made to restrict the press's freedom in Vietnam. The Vietnam War was unpopular among many in Great Britain. Unlike in the United States, whose soldiers, sailors and airmen were fighting and dying daily, most British were not emotionally invested in the war’s outcome. While British press laws are more stringent than those in the United States, those restrictions were rarely exercised. The United States could not control the activities of British reporters who were not dependent upon the American military for logistical assistance and for whom American military press briefings were largely a farce.
http://www.americansc.org.uk/Online/Wilsonjohnson.htm

https://www.frontlineclub.com/vietnam_35_years_since_the_fall_of_saigon/

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