As a serving police officer i can answer your question thus: A caution is not a criminal conviction, you can only get a conviction by appearing in court and being found guilty, even if the court decide that you need not pay a penalty, i.e. they give you an absolute or a conditional discharge. You do not have to disclose a caution unless the question specifically asks if you have received a caution, in which case you should answer it honestly. In my experience the USA will not be interested in a caution for theft. They