I definitely think Oren is on the left side of the Israeli middle, I don't think there can be any question about that.
His tell-all is characterized here as "defiant".
I guess it's kind of a moderate 'screw you' from Oren to Obama, and I agree with the author of this piece that Bibi refusing to denounce ('distance') himself is more screw off icing on the cake, which is pretty Jewlicious.
Related take from the wonderful Free Beacon:
"Reading Oren’s new memoir Ally,
it’s clear that Israel has been on her own since the day Obama took
office. Oren provides an inside account of relations between the
administration of Barack Obama and the government of Bibi Netanyahu, and
his thesis is overwhelming, authoritative, and damning: For the last
six and a half years the president of the United States has treated the
home of the Jewish people more like a rogue nation standing in the way
of peace than a longtime democratic ally. Now the alliance is “in
tatters.”
"The alliance has faltered to such a degree that Oren is morose. He
wonders whether Israel is in the same precarious position it was in
1967, before the Six Day War, or in 1948, when it came close to never
being born. Neither option is comforting. David Horovitz asked him, “Are
people going to look back in a few years’ time and say, ‘This is what
they were talking about in Israel as Iran closed in on the bomb and they
were wiped out?’” Oren’s response: “It’s happened before in history,
hasn’t it?”
"It has. And it may happen again. But whatever happens, thanks to
Michael Oren, history will know that an inexperienced and ideologically
motivated president drove a lethal wedge between the United States of
America and the young, tiny, besieged Jewish State."