"I think her disclosure was adequate, as it assumes those reading her story understand that columnists' jobs are to give their own commentary."
We might have to agree to disagree, then. Without an explicit disclaimer (as is common/conventional for opinion pieces like this), the only reasonable assumption here is that - by allowing this article to be published on its website with its branding - the Washington Post endorses this article and the opinions thereof.
None of what you've linked/quoted contradicts that assessment in any way. In fact, it only reinforces it.
We might have to agree to disagree, then. Without an explicit disclaimer (as is common/conventional for opinion pieces like this), the only reasonable assumption here is that - by allowing this article to be published on its website with its branding - the Washington Post endorses this article and the opinions thereof.
None of what you've linked/quoted contradicts that assessment in any way. In fact, it only reinforces it.