there is no governmental power to "do" something, before they have the actual law behind it to do whatever. again the Constitution is a LIMIT on the federal government, 10th amendment. only WHEN Congress passes a law does the government doing something, assuming its constitutional, become legal.
right now all Trump can do is hope Congress writes a law. writing a law has never been a power of the president. also he needs to hope Congress writes a favorable law, instead of one that works against him.
cops need a warrant to enter my house, unless they have reason to believe in X circumstances. if said cop enters my house, without a warrant and without reason X, he illegally entered my house. just because the cop CAN enter my house legally doesn't mean its automatically legal to do it. even for the government.
at 16 I can legally go get a drivers license, but I can not legally drive a car before I actually get the license, even though I am legally meet the requirements.
congress has the ability to raise taxes. they can not collect said taxes, until they pass the law behind it.
the government doesn't have the power/right to do whatever. UNTIL it passes a law saying it can. so there is no power without the legal backing. that is how the Constitution works, 10th Amendment.