You are certainly not going to find it in that sentence.
Does that mean that your play must be based on a true story? Could be. Or does that mean that your play must be made from the "whole cloth" of your imagination? If the story of your play is made of "whole cloth", it is obviously not true. The question then becomes: How close to the truth do I want my story to be? Or... do I want any part of the truth? If a play is made of "whole cloth" and some truth, this may be where you want to be. Obviously there are many plays written entirely in truth, but if 'Hollywood' gets it hands on it... who knows what will happen.
Where to find your inspiration? In all of your years of personal experience there must be some little bit to inspire you to expand upon. That "little bit" could be a part of something you read recently or as long ago as your childhood. It could be a person. A person who made a life-changing impact upon you or one of your close or distant relatives... or a friend of yours.
Find a quiet place (a park, or your favorite chair) and spend some time alone. Don't take a notebook. Don't take notes until you get to your writing place. Do nothing but think. Most people don't do enough, or for that matter, any "peaceful thinking". Writers need to think... in peace.
Ah! An inspiration: Now that you have found a "little bit" maybe your personal knowledge and experience can expand upon it. Caution: You are not going to find every aspect you will need to expand that "little bit" in your storehouse of knowledge and experience. Resign yourself to that. If your play is to have any future on paper, you will need to research your "little bit" further. If your story has some bit of truth, it must be consistant with the truth.
Notes for ______(Tentative title)______) Inspired by my father's return from "Operation Enduring Freedom". He was a changed man. He was not the man who kissed me good-bye.
Query: What was "Operation Enduring Freedom"? (Research the net: Wikipedia (not totally reliable); George W. ("Dubya") Bush's remark that "...this crusade (bad choice of words given the "enemy"), this war on terrorism, is going to take a while"...).
Query: Why did it happen? (Research the net: Wikipedia.)
Query: How did my father get involved? (Ask Mom.)
Query: How far do I want to take this? The ethics of war? The terror of war and its aftermath? How did it effect Daddy? How did it effect his family? Me? Mom?
I think you get the idea.
Writers need to think... in peace. Find your peaceful place for inspiration.