Taiwan has become the object of a US congressional battle, with a Republican candidate accusing his Democrat opponent in a new TV ad of violating house rules by having lobbyists pay for a US$22,000 trip to Taiwan last year — except there’s a problem: the ad shows the Chinese flag as a backdrop.

The ad, paid for by Republican congressional candidate Matt Doheny, has led to some head scratching in the US and accusations that the “inflammatory” error could mislead the US public.