What we know Thomas Jefferson said

I predict future happiness for Americans if they can prevent the government from wasting the labors of the people under the pretense of taking care of them.

-- attributed to Thomas Jefferson

Whether he actually said that or not is unknown. We do know, however, Thomas Jefferson in 1802 wrote to Thomas Cooper a subtly more profound statement.

If we can prevent the government from wasting the labors of the people, under the pretence of taking care of them, they must become happy.

-- Thomas Jefferson (reference)

Thomas Cooper, like Thomas Jefferson, was a politician and academic. The "we" to which Mr. Jefferson refers, then, are those with political power. Continuing with his logic while linking back to the attribution, it is imperative we are diligent in electing officials who hold, and will act in support of, our beliefs. Unfortunately, at least from my experience, there are too few individuals running for office so inclined.

Reference

TITLE: To Thomas Cooper.

EDITION: Washington ed. iv, 453.

EDITION: Ford ed., viii, 178.

PLACE: Washington
DATE: 1802

http://etext.virginia.edu/etcbin/foley-page?id=JCE2358