Presidential powers: What does a President have the legal power to do?

A Presidential candidate may make a lot of promises in a campaign, but what do they legally have the power to do?

President-elect Donald Trump will have a lot of executive power when he enters office in January. But his powers will only go so far as Commander-in-Chief.

Under existing law, he could bar Muslims from entering the country, according to the New York Times.

The law authorizes him to bar people whose entry is seen as 'detrimental' to the United States. President Reagan blocked Haitian migrants from pouring into U.S. territories in 1981.

A big sticking point for the gas and energy sector is that Trump could change President Obama's environmental policies. He could strike down the Paris Climate Change Agreement and stop existing climate regulations that oil and gas companies claim would cripple business.

There are things Trump cannot do alone. He cannot lower or raise taxes on his own. He must spend money as Congress appropriates, and that could prevent him from trying to "build a wall" that he's been talking about for months, unless he actually gets Mexico to pay for it.