If you an American Citizen, you don't need a visa for upto 6 months of stay. The cheaper BA fare to UK from US is not due to the visa problems for some people, but for people who are care about the miles accrual.
BA does not count miles on tran-Altlantic flights, while all other US airlines does.
BA does not count miles on tran-Altlantic flights, while all other US airlines does.