And clear up into the second term, Donald Trump argued that Barak Obama was not eligible to be president because he didn’t have a valid birth certificate proving his American citizenship. The “birther” issue didn’t stop Obama from being president, and was a waste of breath for years.
Trump took over his father’s [racist] successful construction business and made it so successful that it later became a brand. It’s like saying Ralph Lauren doesn’t know clothes because he no longer sews.
Back to the question:
“How will Donald Trump make Mexico pay for his “wall”?”
Restricting remittances to Mexico.
Taxes and tariffs on Mexican goods.
Raising fees for visas.
These aren’t new ideas. Jeff Sessions, Senator from Alabama formed most of them, and is a key Trump advisor.