That song line from "all the way" is emblematic of The Night We Called It A Day, which starts out as a gritty piece of history, but ultimately becomes a testament to the joys of total romantic commitment.
For much of The Night We Called It A Day, I thought I had the movie completely pegged: Frank Sinatra, representing US Cultural Imperialism, running roughshod over the Australian locals. I'm not thin-skinned, and not uncritical of the US myself, so I thought, okay...that along with the voyeur's pleasure of seeing the crude reality of Sinatra's private life portrayed on screen is sufficient for 90 minutes entertainment.
But what starts out seeming like a poison pen letter turns out to be more of a Valentine, and the switch from one to the other makes the conclusion especially satisfying and exhilarating. The filmmakers play fast and loose with the facts toward the end, but the result is worth the artistic license.
I doubt anyone could play Sinatra and come out on top; in his own films Sinatra had a singular presence that could never be duplicated by any mere actor. Hopper isn't mimicking, however, he is acting, and he does a good job of conveying the essence of his character. I imagine the most difficult part of the role was bringing the audience along in those scenes where Sinatra, without dropping his tough guy act, reveals a tiny glimpse of the sweeter inner man. I bought it.
Maybe I was just in a receptive mood, but I immensely enjoyed it.