If the Constitution had not been ratified, the United States would have likely become a series of separate nations, leading to conflicts and possibly a civil war. European powers may have intruded, and the eventual expansion to the West would have caused further conflicts. The country would have been weaker and would not have played the same role in the 20th century.
Joseph Ellis, of Mt. Holyoke College and author of American Creation, talks about the triumphs and tragedies of the founding of the United States. His goal in the book and in this podcast is to tell a story for grownups rather than for children, where the Founders are neither saints nor evil white, patriarchal slave-holding demons. It is a nuanced story of triumph--a military victory over a seemingly unbeatable vastly more experienced army, the creation of the first geographically large republic, a nation without a state religion, a nation that creates a party system with a loyal opposition, a Constitution with the virtues of ambiguous sovereignty, and tragedy--the failure to resolve the slavery issue, and the tragic conflict with the Native Americans. Some of these outcomes were intended by the Founders, others emerged unintended.