NATO standardization did not make British and American amphibious doctrine identical

Why did Argentina assume Britain used the same amphibious doctrine as the United States?

American advisers reasoned from NATO partnership and shared publications, but British and American formations, capabilities, and operational methods remained materially different.

American advice to Argentina treated NATO membership as evidence that Britain and the United States shared amphibious doctrine. Both used Allied Tactical Publication 8 for command and organizational arrangements. Their operational methods still differed, as the contrasting structures and assigned capabilities of a Royal Marines brigade and a US Marine regiment showed. Shared publications therefore did not establish how British forces would choose to land and fight.