Because he refuses to roll over and allow NATO to plunder Libya using its Al-Qaeda-backed  rebel army
Al Jazeera 
Thursday, May 12, 2011
Italy: Gaddafi arrest warrant coming in weeks
The International Criminal Court will likely issue an arrest warrant for Libyan leader Muammar Gaddafi by the end of the month, Italy’s foreign minister said.
The warrant would be a “key moment” in the battle against Gaddafi and would make it impossible for him to escape into exile, foreign minister Franco Frattini said on Thursday.
“From that moment on, an exit from power or from the country will no longer be imaginable,” he said.
The UN Security Council voted unanimously on February 26 to ask the ICC to investigate human rights crimes in the uprising against Gaddafi, which began earlier that month.
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