Speaking to Lost Souls

Riddled Emotion

I'll bring you to your knees,
                 With a simple thought.

I'll leave you alone and broken,
                 With a simple word.

I'll cling to you and cloud your perception,
                 With a simple suggestion.

I'll creep in and steal your security,
                 With a simple action.

I'll halt the world and bring war,
                 With a simple accusation.

You'll undoubtably know me when I'm present.
Who am I?