This is a charade - look for parts that combine in sequence to build the answer word by word or syllable by syllable.
Break this into parts: 'heads to America' gives you the first part (think of the direction you go to reach America), and 'see below' gives you the second part (what word means 'below'?).
Answer: ASUNDER | 'Heads to America' = AS (going toward America, you head west/as in 'as far as'), 'see below' = UNDER. AS + UNDER = ASUNDER (in bits, torn apart).