That's still possible in a negative sum game; all negative sum means is that the sum of the benefits to all parties is less than the sum of the costs to all par

That's still possible in a negative sum game; all negative sum means is that the sum of the benefits to all parties is less than the sum of the costs to all parties. So if say the US hoses the Mexicans but good it can still come out ahead as long as the Mexicans go down hard.