Is Trump bluffing?
No I don’t think he is.
As President will he have the power?
It’s already law, so yes.
Are we actually giving that kind of money to Mexico?
No. And congress won’t give it to him either
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If we are not giving money to Mexico then Trump is LYING about how he will pay for it.
Are you sure you are right?
Wikipedia says $560MM in foreign aid went to Mexico in 2014.
Yup. If we stop GIVING mexico money and use that money to pay for a wall (asuming congress goes along with it) WE are paying for it. If he taxes out going money sent to mexico that is money from welfare or jobs in the united states and again WE are paying for it.. I see no way mexico actually pays for the wall.