With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: The United States battled in the Vietnam War to prevent the spread of communism.
text_B: David Barton may refer to  :. David Barton -LRB- politician -RRB- -LRB- 1783 -- 1837 -RRB- , U.S. senator from Missouri , serving 1821 -- 1831. David Barton -LRB- author -RRB- -LRB- born 1954 -RRB- , American author , evangelical minister , and political activist. David K. Barton -LRB- born 1927 -RRB- , American radar systems engineer. David K. Barton. David K. Barton. David Walker Barton -LRB- 1801 -- 1863 -RRB- , Virginia politician. David Walker Barton. David Walker Barton. David Barton -LRB- footballer -RRB- -LRB- born 1959 -RRB- , English footballer
not_related.