In case you thought I disagree with you, this might clarify why this is just a difference in tense: If you have malignant cancer, it is "killing you now" (you a

In case you thought I disagree with you, this might clarify why this is just a difference in tense: If you have malignant cancer, it is "killing you now" (you are in the process of dying of something) but only later on will it actually "kill you" (ie. you will become dead).