Who enfoces the law?

I still see comments on Facebook saying we don't have to worry about Trump, we have checks & balances, the other branches of government.

Congress & the Supreme Court may talk, may enact laws and hand down rulings, but it's the executive branch, headed by the president, who is supposed to act on this. They are the ones who sign checks. They are the ones who detain people at airports. They are the ones who arrest people. Saying Nixon backed down doesn't prove that every other president will. It doesn't show us what would have happened if he hadn't backed down.

https://www.nytimes.com/2017/01/29/nyregion/airports-travelers-detained-executive-order-donald-trump.html

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A federal judge in Alexandria, Va., on Saturday ordered government officials to give lawyers access to all legal permanent residents being detained at Dulles. But when lawyers showed border agents there the court order and requested access to detainees, a supervisor replied, “That’s not going to happen.”

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