It's a lot of dry practical advice and then you get the "interacting with Americans" parts and it's stuff like this:

Americans often identify with the countries of their ancestry, even if they themselves and several generations of their immediate ancestors were born in the US. For example, an American of Irish descent may tell you they are Irish if asked their ancestry. This self-labeling is understood and considered correct in the American context, and it would be considered rude to challenge this.

And this, which basically explains that Americans hate America but don't want to hear about it from foreigners:

Many Americans are openly critical of their government and its policies (political debate being a national pastime), but the US is a very large country with all types of people, and some may be offended to hear any criticism from foreign visitors. Most Americans will change the subject or excuse themselves from the conversation if they think you are being inappropriate. If this happens, do not pursue the offending topic further. As a general rule, don't discuss political issues with people unless you're well acquainted with them or if they've asked for your opinion.

Do not insult or speak badly of the country. Although it is legal to criticise the country, many Americans would not appreciate your feedback unless you're well acquainted with them. Some Americans aren't tolerant of criticism of their country, and if theirs is spoken about negatively, it could either result in violence or some harsh words.