Cashing out in dubai

[David Pimenov]

If a u.s. citizen lived and worked in dubai for only one year and then cashed out like 1.4 or 1.6 billion usd even if such money was clean and legitimate, would this amount arouse suspicion once back in the u.s.?  Up to what point would u.s. authorities investigate such origin of funds?  How good are u.s. money laundering laws even if such amount of usd is legitimate?