I read that this memorial shows the two towers but I can’t see it. What am I missing?

If you view the Tear Drop Memorial from the right angle, it frames the location in Manhattan where the old World Trade Towers (2) were. You can see Manhattan (as well as the Statue of Liberty) from the Tear Drop. There are many subtle details about the sculpture.

Your brain

I visited the memorial when I was in NJ

There is only 1 tower

They were identical twin towers.