For Michael Walzer, to be liberal (adj.) is to be capable of recognising and navigating trade-offs; to be nondogmatic; and---not explicitly stated but implied---to be committed to looking for, and exploiting, the opportunities to make everyone better off. In other words, to be liberal is to be a good economist.
Walzer is not shy of wearing his politics on his sleeve. He should not be. After all, his politics is his and has not been thrust upon him by the accident of birth. One is free to broadcast any aspect of one's persona one pleases---the bandwidth of the public square permitting---and to broadcast the aspect that one is wholly responsible for (with a little helps from one's friends and, in Walzer's case, comrades) is the American way.
