Terrorist Plan using Occult Power theorized

What would be the scenario if the terrorist group had  pursued occult power to wage their war against humanity?

There would be limited  target to speak of.

But they have their targets.

The most potent method to be employed must be that of sorcery.

Scenario 1 

The terrorist sorcerers must attack the head of the state to create instability.

At the secret meeting place of the sorcerers they are invoking the power of the occult to make the president of the state to fell  insane or create a force that will make the head of the state to succumb to a dreaded illness. Once the objective was attained, they will now wait for the next successor to sit in, before targeting him again with sorcery. They will eliminate this person again.  When  the next successor will succeed again, it  will be the same target again. 

Through this series of sorcery killing, the state will be put in chaos. The business will be affected and scientific world will be deeply challenged.

But can sorcery affect this modern world?

Nobody knows, but to be wary with this kind of treat is much  better.