Admittedly, I don't know much of the exact parameters of "realpolitik" as it is quite uncommon in the US to use the term, but is it nearly the same thing as "realism"?
I believe his point was that people need to look at things from a more realistic perspective and that reading on the matter would help people gain an understanding of it.
So is an understanding of "realpolitik" not useful for the situation in Syria...? I'm confused.
Realism (with a capital 'R') is a separate, but somewhat related, international relations theory. It is itself broken into several sub-theories. I personally subscirbe to Stephen Walt's "Balance of Threat" Neo-Realist doctrine.
Realpolitick is probably best described as a
pragmatic foreign policy that is devoid of ideology, where the only goal is the increase of one's state's or one's own power and/ or security. A head-of-state which practiced
realpolitick would sign a treaty one day and break it the next if it was to their benefit. Joseph Stalin is likely the single best example in the twentieth century of a successful practitioner of
realpolitick, but once again he was ideological, he just happened to profit from that ideology.
Bismarck is somewhat legendary for his practice of
realpolitick, but it is often wrongly assumed that everything he did was for Prussia's benefit or to achieve some over-arching goal of German unity. In practice, Bismarck was simply out to increase his own personal power. He was also somewhat ideological, though his ideology happened to work in his favour in most circumstances so people discount its actual effect on his actions.
Most nations attempt to practice a combination of
realpolitick and Kenneth Waltz's Neo-Realist doctrine of a balance-of-power based on security (though most heads-of-state likely know nothing about either theory, they're just doing what seems to work most of the time and what everybody else is doing) but considering Waltz's theory is hogwash this doesn't really work. In practice, vested interests often steer a foreign policy in completely non-Realist directions. Liberalist doctrine is especially popular in the US, with Bill Clinton's neo-Wilsonian attitudes being the foremost example.
Realpolitick would work in regards to the Syrian situation, but first one would have to posit a goal for the foreign policy in question before one could determine the best method of achieving that goal through
realpoltick.
EDIT:
I would, but I would consider the "backing into a corner" to be pressure from the people.
It was more from Congress, really.