NORAD officials have maintained that they would have intercepted and shot down United 93.
( ( NORAD officials ) ( ( have ( maintained ( that ( they ( would ( have ( ( ( intercepted and ) shot ) ( down ( United 93 ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP NORAD) (NNS officials)) (VP (VBP have) (VP (VBN maintained) (SBAR (IN that) (S (NP (PRP they)) (VP (MD would) (VP (VB have) (VP (VBN intercepted) (CC and) (VBN shot) (PP (IN down) (NP (NNP United) (CD 93)))))))))) (. .)))
NORAD believes that they would have changed their minds on how to deal with United 93.
( NORAD ( ( believes ( that ( they ( would ( have ( ( changed ( their minds ) ) ( on ( how ( to ( deal ( with ( United 93 ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP NORAD)) (VP (VBZ believes) (SBAR (IN that) (S (NP (PRP they)) (VP (MD would) (VP (VB have) (VP (VBN changed) (NP (PRP$ their) (NNS minds)) (PP (IN on) (SBAR (WHADVP (WRB how)) (S (VP (TO to) (VP (VB deal) (PP (IN with) (NP (NNP United) (CD 93)))))))))))))) (. .)))