President Obama today signed into law a bill dubbed the "Former Presidents Protection Act of 2012," which restores lifetime Secret Service protection to former presidents elected after 1997.

It also provides for protection of all children of former presidents until they reach 16. Congress passed the bill last year -- it was introduced by Rep. Trey Gowdy, R-South Carolina, who said presidents' longevity and "the war on terror" make it necessary. He noted that presidents elected after 1997 had only been authorized to receive Secret Service protection for 10 years after leaving office.

"The increased mobility and youth of still-living former Presidents, coupled with the national security threat posed to post 9/11 leaders who were instrumental in the war on terror, necessitates protection for life, as has been the case since the 1960's," Gowdy said.

Secret Service protection was once for a lifetime, but Congress changed the law in the 1990s so that any president elected after Jan. 1, 1997, and his or her spouse were to receive the federal protection for only 10 years. George W. Bush would've been the first president to face a limit on protective services.