The classical liberal order has a paradox at its heart. It provides everyone the liberty to pursue their own happiness. Yet it needs enough public spiritedness and virtue to maintain the order that permits the pursuit of liberty. Many internal institutions in the liberal state try to address this paradox, including the Constitution, but external factors play a role as well and one of the most important is the presence of children.
One problem for the liberal order is that individuals and groups so often consult their own interest rather than the public interest in the public sphere. At the federal level, the mild supermajority rule created by tricameralism (the two houses and the President) and stronger supermajority rule for constitutional amendments try to address this by making enactments hard to repeal. This legislative stickiness creates something of a veil of ignorance. People are not as sure where they will be in the future and thus are more likely to consider the public interest rather than their private interest in deciding whether to approve them. Children help thicken the veil of ignorance. The position of one’s children is even more uncertain than one’s own.
Classical liberal democracies also have an innate tendency to overspend and over borrow.