What happened? Why wasn't it built? I honestly don't know.
Update from Kevin Roche's office: After excavation had begun an adjacent office building became available, which the bank elected to purchase instead of completing this project.
Something was built though, this...I believe it is the Hotel Reserve NYC. Obviously built with a completely different program and with no civic responsibility.
"...The fourth objective has to do with planned development on the lower tip of Manhattan. These are enormous projects, the two towers of the World Trade center near Battery Park, the US Steel Building under construction, the the existing towers [Chase Manhattan and Marine Midland]. Our building will be surrounded by these monsters. They would place us in a hole. From the occupant's point of view, he would be in a canyon."
-K. Roche, 1970
Skyline from Brooklyn's new park. The top of Roche's tower would have stuck out, in line with SOM's Chase Manhattan Building, not lost in the canyons of Lower Manhattan.
I did place a call to Kevin Roche's office for additional information. Seems they're busy, that's a good thing I guess. But they're going to get back to me in the next week or two. Hopefully with the back story as to why the project wasn't completed. Stay tuned. Also this is a continuation of the MIT Press's Perspecta 40: Monster. I highly recommend picking up a copy.