I will not allow, what is not in my control,
to prevent me from doing what is, in my control.
This is my motto in life by which I have lived all my life. I always try to focus on what I can do no matter whatever else I can’t do. I do that because of one reality that is common and uniform for everyone. And that is, that no matter how powerful or powerless you may be, there will always be things that you can do and things that you can’t. If you focus on the things you can’t do, they will drag you down and prevent you from even trying to do what you can. This is incidentally a copout justification strategy that many people use. 

They globalize an issue which then allows them to legitimize their own inaction. They ignore the fact that every issue starts with the individual. But localize the issue and you immediately see a way in which you can make a difference. Coping out may seem cool or even be the first thing you do, but it disempowers you, makes you frustrated and stressed. Localizing your view shows you what you can do. It empowers because it shows you that you are still in control, you still have power. It is however not good for those who want to copout because it takes away their excuses for sitting silently by instead of taking positive action. It is uncomfortable, energizing and powerful and so it brings about change.
Let me give you an example. If I ask you what you are doing to solve global issues of poverty, illiteracy and environmental destruction, you will probably look at me with the quizzical look that people give to those they consider to be borderline insane. “What a strange question? Is he crazy? What am I doing about global poverty, illiteracy, blah, blah? Why not also ask what I am doing about disarmament, stopping wars, global warming, Crazy man!” Maybe this is what you are thinking. 

But if I rephrase my question, or if you do it in your mind to say, “What can you (and I, before you) do to help one poor person, teach one child (or adult), stop using plastics or switch off an unneeded light?” Then it immediately makes sense. Multiply that and you have a global phenomenon.
A tidal wave is a ripple, magnified.
Yesterday has gone with whatever it contained. Tomorrow is not here yet. All I have is today so let me see what I can do with it. The past has a very important role; to teach us lessons about what to do and what to avoid and to give us encouragement for the future. Beyond that to live in the past is detrimental to the future.

Resting on laurels makes them go flat. Brooding on sadness pulls down the heart. We need to be grounded in the present with our eyes on the future. Our past does not determine if we will succeed or fail. It merely indicates where we need to start.