An important part of U.S. diplomacy is getting sovereign states to work together voluntarily.
( ( ( An ( important part ) ) ( of ( U.S. diplomacy ) ) ) ( ( is ( ( getting ( sovereign states ) ) ( to ( ( work together ) voluntarily ) ) ) ) . ) )
(ROOT (S (NP (NP (DT An) (JJ important) (NN part)) (PP (IN of) (NP (NNP U.S.) (NN diplomacy)))) (VP (VBZ is) (VP (VBG getting) (NP (JJ sovereign) (NNS states)) (S (VP (TO to) (VP (VB work) (ADVP (RB together)) (ADVP (RB voluntarily))))))) (. .)))
U.S. diplomacy would fail if the states didn't work together.
( ( U.S. diplomacy ) ( ( would ( fail ( if ( ( the states ) ( ( did n't ) ( work together ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP U.S.) (NNP diplomacy)) (VP (MD would) (VP (VB fail) (SBAR (IN if) (S (NP (DT the) (NNS states)) (VP (VBD did) (RB n't) (VP (VB work) (ADVP (RB together)))))))) (. .)))