British action wouldn't have mattered.
( ( British action ) ( ( ( would n't ) ( have mattered ) ) . ) )
(ROOT (S (NP (JJ British) (NN action)) (VP (MD would) (RB n't) (VP (VB have) (VP (VBN mattered)))) (. .)))
If Britain got involved, things would have gotten worse.
( ( If ( Britain ( got involved ) ) ) ( , ( things ( ( would ( have ( gotten worse ) ) ) . ) ) ) )
(ROOT (S (SBAR (IN If) (S (NP (NNP Britain)) (VP (VBD got) (ADJP (VBN involved))))) (, ,) (NP (NNS things)) (VP (MD would) (VP (VB have) (VP (VBN gotten) (S (ADJP (RBR worse)))))) (. .)))