Interesting observation. He definitely did take it personal. I haven't read the book in alot of years but of course the movie is vivid in my mind like I saw it yesterday. The "strictly business" line is better movie line for sure and its genuine to real CN but they didn't really explore who, mentally how he got to that 'understanding' of the life. Obviously being a military man he understood strategy and powerplays but the "mafia mentality" is very specific thought process, they delved into alittle when Vito had the "Traitor" conversation with Michael