That's a great question. One that I wish our nation and global human collective would ask itself far more earnestly that it does.
I would say our #1 problem right now is that our technological prowess has far, far outstripped our ethical prowess, to the degree that on several fronts, we are in danger of literally destroying ourselves and perhaps destroying the ecosphere of the entire planet. Currently, we are the only known expressions of "intelligent life" in the universe, and we are teetering on the edge of extinguishing it by our own hand.
I would say that out #2 problem is that we don't live long enough as individuals to apply what we learn over the course of our lives to the well-being of life and humanity in general. And as a result, every generation keeps making the same mistakes over and over and over. When, I believe, if we lived twice as long as we do, the second half of our lives could be spent actually applying the wisdom we acquired in the first half, because most of the survival tasks would be taken care of. The children would be raised, the wild oats have been sown, the heartbreaks and disappointments will have been put to rest, and we would still have some time and energy to actually do some good in the world. As it is, by the time we've gained some actual wisdom and common sense in life, we're too old to apply it effectively to the universal human endeavor.
And if I were to choose a 3rd universal human problem, I would say that it's the sudden and overwhelming degree of abstraction in most of our lives, as modern humans, causing us to become somewhat "insane" without even realizing it.
People living in the modern nations of the world have become so specialized and removed from the task of survival that most of them could not survive if the abstract, inter-related societies in which they live were to collapse or fall apart. Which they could do very easily. Almost none of us could build our own shelters, hunt our own food, make our own clothes, or defend our own lives if it were to become necessary. And because we don't know how to do these things, or even think about them, anymore, we have little cognizance or respect for the affinity with nature that goes along with such an elemental lifestyle. And we become too easily willing to poison and destroy the very natural habitat that we need to survive. We are getting lost in all this abstraction, and we are becoming literally insane as a result. We think money is more important than clean air and fresh water. Which is truly insane.