If hypothetically, your goal was to find the cure for cancer, but when you were talking to the researchers they wouldn't give you the information, so you threatened them with a gun, the means by which you obtained the cure are bad, but the end-product of that bad action is good. I believe that in ethics one action cannot cancel out another, that they are two different actions individually. If the means were bad but the end was good, the end does not justify the means, but the means take away some of the sincerity of the end.

I agree that the word "happy" refers to satisfaction whereas the word "good" refers to fulfillment. I also believe that the word "happy" pertains to humans and other living creatures with minds that are capable of feeling. Happiness is generally referred to as a feeling of satisfaction and the word "good" is generally referred to as the functionality of an inanimate object. In some respects they are similar, but they are different and should not be used as if they had the same meaning.

I voted political corruption because a lot of the problems listed could be caused by it. For example, nuclear weapons are misused under corrupt political leaders (although it is debated if there is a correct use for them at all) and corrupt politicians can also plunge us into poverty and start dangerous wars. Miscommunication is also one of the main causes of war in my opinion. When everyone is telling you a different truth, it is difficult to come to your own conclusion as you can often unconsciously take their view into consideration. If poor upkeep of heavily populated areas is contributed to by political leaders, it can lead to epidemics. I think terrorism will always be there, in some way or another, although I am continuing to theorize about that. It seems that the best leaders are the ones that do not desire to be in a position of power in the first place. Either way, after humanity decides on one way to destroy our existence, the world moves on, the sun will always rise and set, and the Earth will meet its end, as all living things do.