can't resist given the context, but it should be embarrassing for whom.
When one says a text is embarrassing there are generally three potential objects of embarrassment, the writer, the reader, or, if there is one, the target of the text.
In the case of a manifesto the manifesto writer intends for the target of the manifesto to be embarrassed, but often the actually embarrassed is the unsuspecting writer and the cringing reader.
>> the manifesto writer intends for the target of the manifesto to be embarrassed
Huh? Citation please.
(and good catch on 'whom')