A friend is trying to complete the US ESTA application for a trip to Mexico.
They will be flying in to LAX and then driving to Mexico the same day, and on their trip home they'll be driving from Mexico to LAX to fly out.
I would be inclined here to check "Yes" to being in transit to another country, however potentially (unsure at this stage) they will also spend some day-trips sight-seeing in California between those two in-bound/out-bound legs. In that case the "in-transit" wouldn't be correct.
The ESTA is also valid for 2 years, in which they are likely to return to the US for tourism.
What is the correct way to answer this question, knowing that the sight-seeing and further tourism is possible to happen, although unplanned at this point? Is there an easy-to-read guide to explain how to answer?
Possibly relevant information - my friend will have a flight to the US, and then a flight from the US 5 weeks later. There are no other flights from/to the US in that time, so potentially it looks (to CBP at least) like a 5 week long trip to the US