“Godwin’s Rule of Nazi Analogies,” as it is widely known on the Internet, states that as any online comment thread grows longer, “the probability of a comparison involving Nazis or Hitler approaches 100%.” With all due respect to American internet-law pioneer and free-speech advocate Mike Godwin, perhaps the law ought to be renamed after Turkish Prime Minister Recep Tayyip Erdogan, who might just be the world’s most verbally promiscuous trivializer of the Nazi legacy.“Just like Hitler, who sought to establish a race free of all faults, Israel is chasing after the same target,” Mr. Erdogan recently told supporters at a...