It's all well and good to say that we cannot let people starve in the streets so we need to give them money, but why does the government need to do this?

What about other social issues? What about if the South Texas Project 2.5GW reactor went belly up and spewed all over Houston? Would you being willing to donate extra to cover all the additional social costs of this? What about next year? Or 10 years down the line? Do you think that everyone living in Seattle would donate? Or those in NYC? Again, what about 10 years down the line?
Just for reference, the current social welfare costs of Chernobyl are about 5-7% of Ukraine's GDP. It's probably costing Russia and Belarus similar amounts, since Chernobyl is on the border of the three. This is 17 years after the accident .