You've been arrested. You've admitted guilt. The US London Embassy website says you should apply for a visa.
Your offence doesn't sound like moral turpitude thougn - which means that there shouldn't be a problem in getting one.
And you could still quite truthfully tick the 'no' box on the ESTA form and not worry about a visa at all. The London Embassy statement is advice, not law, and is made because they (quite rightly) don't trust the British public to understand what moral turpitude is - or to answer truthfully if they do. But you are entitled to make your own decision on the matter.