In the United States, the requirements for the military draft, also known as conscription, are governed by the Selective Service System. Here are the key requirements and details:

Who Must Register:

1. Age and Gender:

   • Men: All male U.S. citizens and male immigrant non-citizens residing in the U.S. who are ages 18 through 25 are required to register with the Selective Service System.
   • Women: Currently, women are not required to register for the draft.

2. Citizenship:

   • U.S. citizens, including those living abroad.
   • Immigrant non-citizens, including permanent residents (green card holders), refugees, asylum seekers, and undocumented immigrants.

3. Exceptions:

   • Men on active duty in the U.S. Armed Forces.
   • Cadets and midshipmen at the U.S. service academies.
   • Some individuals with certain disabilities.

How to Register:

• Online: Registration can be completed on the Selective Service System's website.
• By Mail: A form (SSS Form 1) can be completed and mailed in.
• At the Post Office: Forms are available at any U.S. Post Office.
• When Applying for Federal Student Aid (FAFSA): There is an option to register through the FAFSA application process.

Consequences of Failing to Register:

• Legal: Failing to register is a felony punishable by up to five years in prison and/or a fine of up to $250,000.
• Civil Penalties: Ineligibility for federal student aid, federal job training, federal employment, and U.S. citizenship for immigrants.

Draft Process (if reinstated):

1. Lottery: If a draft is activated, a lottery system based on birth dates would be used to determine the order of call.
2. Classification: Individuals called would be classified to determine their eligibility and deferments or exemptions.
3. Induction: Those classified as eligible would be inducted into the military.

Deferments and Exemptions:

• Student Deferments: Full-time students may receive deferments until they complete their studies.
• Medical and Psychological: Those with certain physical or mental conditions.
• Conscientious Objectors: Individuals who oppose war based on religious or moral beliefs.
• Hardship: Individuals who provide essential family support or have other significant hardships.

Recent Developments:

• There have been discussions and legislative efforts to potentially include women in the draft registration, but as of now, no such change has been enacted.

For the most up-to-date information, it's recommended to check the official Selective Service System website.