(S (S (BASENP (DT The) (NN issue)) (VP (VBZ goes) (PP (TO to) (NP (NP (NP (BASENP (NNP Canada) (POS 's)) (NN sovereignty)) (PP (IN of) (BASENP (PRPD its) (NNS citizens)))) (CC and) (NP (BASENP (DT the) (NNP U.S.) (NN sovereignty)) (PP (IN of) (BASENP (PRPD its) (NN airspace)))))))) (PERIOD .))