The "Giant Sucking Sound" was Ross Perot's phrase for what?

The "Giant Sucking Sound" was Ross Perot's phrase for the North American Free Trade Agreement (NAFTA). This was an agreement signed by Canada, Mexico, and the United States. It created a trilateral trade bloc in North America. The agreement came into force on January 1, 1994, and superseded the 1988 Canada–United States Free Trade Agreement between the United States and Canada.

Perot coined the phrase during the 1992 US presidential campaign. He said it referred to the sound of US jobs heading south for Mexico if the free-trade agreement goes into effect. In the second Presidential Debate, Perot argued:

"We have got to stop sending jobs overseas. It's pretty simple: If you're paying $12, $13, $14 an hour for factory workers and you can move your factory South of the border, pay a dollar an hour for labor, ... have no health care—that's the most expensive single element in making a car— have no environmental controls, no pollution controls and no retirement, and you don't care about anything but making money, there will be a 'giant sucking sound' going south."

"... when [Mexico's] jobs come up from a dollar an hour to six dollars an hour, and ours go down to six dollars an hour, and then it's leveled again. But in the meantime, you've wrecked the country with these kinds of deals."

Perot lost the election, and the winner, Bill Clinton, supported NAFTA, which went into effect on January 1, 1994.