Thoughts on Massive evacuation

I do not know for what reason but I keep worried about the state of evacuation in case of an emergency either of a natural disaster or artificial. Our cities are highly populated and there are small island crowded. Why is there no evacuation plan to move great numbers of people across international borders? In case of Earthquakes that come unawares there is no time to move but in case of a flood warning or hurricane, why is there no system to move people across borders. I guess every country is struggling to deal with its own problems.

What about United Nations or the NATO? What if scientists have found that this big hurricane is going to wipe the population from the small island? Will we allow them to die there without any help? Nations must allow more refugees into their countries especially the prosperous ones. Nations naturally do not want to waste their resources and tax money to fund others problems. That is a reason why a tax should be levied on people as an international fund for emergency services for cities or islands or nations under constant treat to disasters.

I would like to know if there is any such fund already in place? May be the United Nations web site can give me more information. So much money goes to waste in wars and weapons that there is no money left for useful purposes. It is as if money cannot be used for useful things. Progress comes in bits and pieces.