For the people that are inevitably going to ask why we are issuing this warning to an enemy, this warning will serve as proof of a forewarning to the Russian citizens and that the attack could have been prevented. Whenever Putin took power, he used a series of staged apartment building explosions to unify support under the guise of terrorism. Russian citizens even found explosives planted on the building they were going to blow up next and there were pieces of equipment and markings used by the Russian intelligence agency on the explosives. The official response is that they were not real and it was going to be used for a training exercise…in the middle of a series of attacks using explosives on apartment buildings.

So the US intelligence community is trying to prevent Putin from being able to allow this attack on his people and use it to garner support based on fear and an affirmation that the Russian people are under attack by outside entities.