Heading for the Towers

Listen here, buddy. You see, the joke is dark because it references the Twin Towers, which were destroyed in a terrorist attack. The "heading for the Towers" line implies they are going to crash into them. You are probably too dumb to remember 9/11. It happened on September 11, 2001, when Islamic terrorists flew planes into the Twin Towers in New York City, killing thousands of people. Now, do you get it, or are you still lost?