Remain? The US was not a relatively isolationist, laissez-faire nation in the first place.
In 1790, the First Bank of the United States was proposed by the 1st US Secretary of the Treasury in the 1st session of the 1st Congress. The tenets of what came to be known as the American System or National System (federal banks, internal improvements, etc.) were supported by the Federalist, Whig, and Republican Parties and such men as Alexander Hamilton, John Jay, James Madison, John Adams, John Marshall, Henry Clay, John Calhoun, John Quincy Adams, and Daniel Webster.
Far from being isolationist, the US was expansionistic and often interventionist. Examples of expansionism are the Louisiana Purchase (under Thomas Jefferson), West Florida (under Madison), East Florida (by John Quincy Adams during the James Monroe administration), Texas annexation (under John Tyler), Mexican-American War (under James Polk), public willingness to fight Britain over Oregon, the Gadsden Purchase (under Franklin Pierce), and the failed Ostend Manifesto (by James Buchanan and others).
Examples of US interventionism start in 1804 during the first Barbary War with the US attempting to replace the ruler of Tripoli with a more friendly candidate and continue from there. Then there are government positions like the Monroe Doctrine and popular movements like Manifest Destiny.
So to make the US into laissez-faire, non-interventionist country, you’re probably going to have change or eliminate the views of all of these individuals and groups. Note that this abbreviated list includes half of the 1st US Cabinet, the 1st Chief Justice of the Supreme Court, and the 2nd, 3rd, 4th, 5th, 10th, 11th, 14th, and 15th Presidents of the US.