Sue, at least one conspiracy theory is exactly right. When I went to Boot Camp in San Diego in 1971, I had a service number. When I graduated boot camp at the end of July 1971, we transitioned away from service numbers and to SS numbers. Since Obama would have been 10 years old, born in 1961, why on earth would he need a service number? The requirement to register was stopped in 1975 but then restarted by Jimmy Carter in 1980 due to the Soviet invasion of Afghanistan and Obama would have been required to register at a local Post Office the week of July 28, 1980.