Everyone is jumping on Brian Williams for his obvious misstatements. Mr. Williams is not a stupid man. Therefore it is perplexing that he would, over the years, consciously make up stories that could easily be disproved.
There is another possibility. He could have FMS — false memory syndrome. This is a common disorder and manifests with confabulated memories, which are false memories that the person actually believes. This would explain his weak apologies: He actually believed the events took place.
We should not be in such a hurry to judge Mr. Williams.