Come on, OP! As a PM, and formerly DM, with 1.7 MM, you should know better than to accept a 45 minute connection to an international flight!!!
Somewhere between 2 and 2.5 hours is my personal minimum connection time. If it happens to be longer than that, then you always have the SkyClub as an oasis and work area. As stated by others, get out of Atlanta earlier or prepare yourself for the possible alternatives (connect via AMS or CDG or maybe even FCO, or spend the night in NYC

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I am sure there was a reason ($$$) why you didn't book the ATL-FRA non-stop!?!?