If Venezuela falls, there will be void to fill. Why do we care? Because we don't want that void to be filled with bad players who will take over and cause more havoc in the region.
Venezuela used to be an oil-rich nation with a high standard of living. It has been brought to its knees by the forces of Chavez and Maduro. They have taken gold and made it into dirt.
We will want some say in who fills the void so we don't have to deal with an enemy who will cause more disruption and chaos to not only Venezuela's future, but to the countries around it in the Western Hemisphere.
Not to speak of the Venezuelan people who have seen their once thriving nation destroyed before their very eyes by socialists and communists.
If your neighborhood was disrupted by bad people who moved into a house and dealt drugs and committed crimes and brought a blight to your once placid home, you'd want to do the same.
That is why we should care.