President-Elect Barack Obama's chief of staff, Rahm Emanuel, co-authored The Plan: Big Ideas for America. This excerpt is from pages 61-62:

It's time for a real Patriot Act that brings out the patriot in all of us. We propose universal civilian service for every young American. Under this plan, All Americans between the ages of eighteen and twenty-five will be asked to serve their country by going through three months of basic training, civil defense preparation and community service...

Here's how it would work. Young people will know that between the ages of eighteen and twenty-five, the nation will enlist them for three months of civilian service. They'll be asked to report for three months of basic civil defense training in their state or community, where they will learn what to do in the event of biochemical, nuclear or conventional attack; how to assist others in an evacuation; how to respond when a levee breaks or we're hit by a natural disaster. These young people will be available to address their communities' most pressing needs.

Just a little reminder, here. Amendment 13 to the United States Constitution reads:

Section 1. Neither slavery nor involuntary servitude, except as a punishment for crime where of the party shall have been duly convicted, shall exist within the United States, or any place subject to their jurisdiction.
Section 2. Congress shall have the power to enforce this article by appropriate legislation.