Changes in US Secret Service protection for presidents over years

During Abraham Lincoln's presidency, anyone could come to the White House and see him. Come they did: mothers looking to have their sons released from military service, wives urging that their husbands be freed from prison after resisting the draft, others who simply wanted to meet the president.

Some only wanted comfort in a terrible time, and that he freely gave," James B. Conroy wrote in his book "Lincoln's White House: The People's House in Wartime."

The world has vastly changed since the 1860s, and so has protection for presidents. Protective details have grown in size, responsibility and technology over more than a century of the Secret Service protecting presidents.

When presidents leave the White House, they are accompanied by a phalanx of Secret Service officers and agents. Cars can no longer drive past what is often dubbed the people's house at 1600 Pennsylvania Ave. The fence has been raised, and don't even try to get past the gate without an appointment or badge.

The ..