In order to arm themselves, Hamas built more than 1,000 smuggling tunnels under the border with Egypt . There are also attack tunnels that reach under Israeli residential areas in communities close to the Gaza border. Terrorists can use these tunnels to suddenly emerge from under the homes and playgrounds of Israeli civilians, spreading death and destruction without warning. Attempts to carry out such attacks have already been thwarted in the present conflict.
The main goal of ‘Operation Protective Edge” is to destroy these tunnels which is impossible to do with air strikes. Therefore Israel is conducting a large ground operation.