The freedom of speech is stated in the first amendment of the bill of rights, which gives you the right to speak anything without the government punishing you.
But, the only thing that the first amendment doesn't say is that you can't speak lies, like if you were to yell in the theater "FIRE!," then cause it would cause danger to the people around you.
That is why if you forget just think speech is key in the first amendment.
The Mexico–United States barrier is a series of vertical barriers along the Mexico–United States border aimed at preventing illegal crossings from Mexico into the United States.
