Polk County Sheriff Bill McCarthy has just returned from Israel, chosen by the National Sheriff's Association to learn about homeland security measures. McCarthy talks about the experience, including learning about the mindset of suicide bombers and new security technologies. Later, members of the U.S. Secret Service are in the state, providing security for President Obama's central Iowa campaign stop. Ben talks with former secret service agent Dan Emmett about what it takes to protect the nation's top executive. Emmett is the author of Within Arm's Length, that chronicles his experience protecting both president Bush's and President Clinton.