I'm not surprised by this. For years, the US and its allies have been sneaking into Russia's backyard. I guess it's fair for them to do so. Venezuela would be crazy to go down the path of developing nuclear weapons. It's not just the US that will fear any such development. Countries in that region will certainly be rattled by such a development and may provoke war.
I don't think Venezuela would be crazy to develop them at all. Once a country has nukes they become almost impossible to consider attacking, couple that with the fact they have one of the largest deposits of oil in the world so it makes it painful to sanction them. But this is a civilian nuke program for the time being so that's a separate story.
If I were the president I would wait a while and then offer to build a nuclear plant in Georgia or even the Ukraine. In return ask military base and to put some anti-ballistic missiles in their country. I'm sure as soon Russia would be happy to stop selling weapons and building the reactor in Venezuela if we promise not to do the same in their backyard