Credit—which stems from the Latin root “credo,” meaning belief—is very emotional and dependent on psychology.
The Republican credo that theirs is the party of patriotism goes back a long, long way, at least to the 1920s.
The "say anything" credo of the Romney campaign continues and mushrooms.
late 12c., from Latin, literally "I believe," first word of the Apostles' and Nicene Creeds, first person singular present indicative of credere "to believe," perhaps from PIE compound *kerd-dhe- "to believe," literally "to put one's heart" (cf. Old Irish cretim, Irish creidim, Welsh credu "I believe," Sanskrit śrad-dhā- "faith"). The nativized form is creed. General sense of "formula or statement of belief" is from 1580s.