I was also puzzled by his hissing "esses" at the ends of plural words and anything else that ends in an "s". Sometimes he sounds like the snake in Jungle Book.
All this puzzlement was cleared up today when I heard a clip of Reverend Wright screeching his anti-American tirade. After all these months of listening to President O speak, and not having heard the Irreverent Wright tape since last fall, it occurs to me that Mr. O has copied the disturbed preacher's oratory style. And now that I realize where he acquired those two bad speech habits, it also becomes clear that the content of his speeches worldwide is just as anti-American as what Wright said in church, just without the curse "God damn America". Since the president has yet to say something about the greatness of the United States in public speeches, it seems that he has the same resentful, hateful sentiments as well as identical sibilants and pretentious "ihs'. That's a miracle, since he "never heard" Rev. Wright curse America.
Addendum, June 10th: I hope Rev. Wright is banned by the U.K., as Michael Savage is, from entering their country. He hissed about "those Jews" this morning, and today, a white supremacist (not "right-winger"--it is the left-wing that hates Israel) man shot up the Holocaust Museum, killing a guard and injuring others. In fact, there has been absolutely NO violence incited by the brilliant PhD. Michael Savage, and there will not be. The woman who put him on the list, Jacqui Smith, is now resigned because of her corruption, a pathetic has-been, and it is our Secretary of State Hillary Clinton's duty to undo the damage. The silence is deafening!
I was wondering why I hadn't noticed anyone else cringing when President O hisses his "esses" at the ends of plural words, so, as the Neanderthal man suggested, I did a little research and came up with this article by Mychal Massie, from August 2008, entitled, "O---- Hissing".