Alaska–although the “Eastern” bit is arguable, since we could declare the International Dateline the border of East and West instead of 180° Longitude. BUt to avoid hassles, we’ll use the longitude rather than the Dateline.
If the Dateline is the East-West border, then Maine becomes the Easternmost state. Hawaii is out farther west (in miles) into the Pacific, but, because Alaska is up where all the longitude bunches together, it is clearly the most western state.
Nihau, HI is just East of 160° 30’ W longitude. (Even Midway Island is only at around 177° W.)
Attu, AK extends out to around 173° E longitude.
Yeah, I can actually understand that now. The further north you are closer the longitudes are bunched. It’s quite a strange concept to get your head round…