I could go into detail about my thoughts about it, but I won't other than to say he was masterful with his humor, his pointed jibes at the President, and his homage to Jimmy Stewart as done by Bob Newhart.
I will however link to a piece by Stuart Schneiderman, giving his analysis of both Eastwood's speech and the reaction by the ever humorless Left.
A small portion of his post:
Representing President Obama by an empty chair is salient, high concept, and very much to the point.'Nuff said.
It offers an image that conceptualizes the Republican critique of the Obama administration. It says that President Obama has failed to lead and has failed to discharge the duties of his office because he is more interested in being out and around campaigning than sitting at his desk in the oval office being the president.
Obama and his campaign staff were sufficiently torqued by the trope to have felt a need to tweet back a picture of the president at a cabinet meeting.
When you have to point out that the chair is occupied, that means that it isn’t.