(S (S (NP (BASENP (DT The) (NN issue)) (PP (IN of) (BASENP (NN immigration)))) (VP (VBZ has) (VP (VBN become) (NP (NP (BASENP (DT a) (VBG polarizing) (NN subject)) (PP (IN in) (BASENP (DT the) (NNP U.S.)))) (CONJP (COMMA ,) (CC and)) (NP (BASENP (NN one)) (SBAR (WHNP (WDT that)) (S (VP (VBZ has) (VP (VBN been) (NP (BASENP (DT an) (JJ intrinsic) (NN part)) (PP (IN of) (NP (BASENP (DT the) (NN fabric)) (SBAR (WHNP (WDT that)) (S (VP (VP (VBZ makes) (PRT (RP up))) (BASENP (DT the) (JJ American) (NN society))))))))))))))))) (PERIOD .))