I hear what is said with respect, however, for UK citizens and those too from Germany I am sure, if only visiting for a period of less than 90 days, or on legitimate business, an ESTA is required and they last for two years. We have had several since they were introduced back in 2009. Below is further information for anybody still in doubt!
The visa waiver program is a U.S. government program that enables citizens and nationals from the 38 Visa Waiver Countries to enter the United States for tourism or business purposes for up to 90 days without obtaining a visa. The advantage of entering the United States under the visa waiver program is that you can travel to the United States on short notice without obtaining a visa in advance.
What is ESTA?
ESTA stands for Electronic System for Travel Authorization. ESTA US visa waiver is an online application system developed by the United States government to pre-screen travelers before they are allowed to board an airplane or ship bound for the United States. Starting on January 12, 2009, any person entering the United States under the visa waiver program is required to hold an approved ESTA US visa waiver Travel Authorization.
Who Needs to Apply for ESTA?
All travelers entering the United States (by air or sea) under the visa waiver program are required to hold a valid ESTA USA visa waiver. The purpose of ESTA US visa waiver is to allow the US Department of Homeland Security to pre-screen all Visa Waiver Travelers before they leave their respective countries. U.S.-bound travelers are recommended to apply for a Travel Authorization at least 72 hours prior to departure.