Knocked Over jokes

What happened when two invisible giants knocked over their blocks?

9/11.

What did Osama say after knocking over the Twin Towers?

He he he haw.

Why did the cow knock over Johnny?

Because the cow felt like to dumb.

My brother and I were roughhousing and accidentally knocked over our bookshelf. My mom came in and started asking who knocked it over, to which I replied that I only had my shelf to blame.

Hey, can I axe you a question?

My brother likes to build "traps" to capture our cat so he can pet it. I said it wasn't gonna catch anyone, he replied with "not going to stop who?" I told him not to worry that it could capture any two.

Why were the Twin Towers knocked over? Chuck Norris was leaning on one of them.