Hello! I'll be traveling in August from Amsterdam to Miami via Atlanta, and i'm worried my connection is too short to make it through.

I'd be arriving at ATL around 7-8 pm, i don't know if it's usually busy at that time. My main worry is having to make it through security+border patrol, since i'm entering the US i'll probably need to retrieve my luggage, pass it through sorts of a luggage control, and then go through immigration, am i right?

In case i miss my connection, since it's all in one ticket and i bought it on the airline's page, should i expect them to get me on the next available flight (that is with available seats) or would they blame it on me? Flying with Delta btw. I know that Europe Union regulations would make it the airline's responsibility, but i don't know how passengers right's work in America.

Also, do airport personnel provide any kind of aid to those about to miss a connection? Again, i've seen people being rushed around gates and through immigration lines in european airports.

I considered changing my connection but that would mean spending the night at the airport and friends have told me it's not very nice to stay at?

Thanks in advance and sorry for the long post!