Just thought this was interesting, from Wiki;

The Earth Alliance and ZAFT started war on 11 February CE 70 after the EA's predeccessor, the United Nations was wiped out by a terrorist attack in the Tragedy of Copernicus on 5 February. On 14 February, the Alliance used nuclear weapons to destroy the PLANT colony at Junius Seven, in what became known as the Bloody Valentine Incident.

It doesn't say who the terrorists were, but either they were an excuse to attack PLANT, or Blue Cosmos did themselves to take over.



"Later, Mina and three of her Socius clones joined forces with the Junk Guild and Serpent Tail (whose roles in Gina's death she remains unaware of) in a failed attempt to stop the "Break the World" terrorist attack by shooting Junius 7's remains with GENESIS Alpha."