The shooting of Rep. Gabrielle Giffords (D-AZ) on Saturday at a shopping center meeting with constituents was a rare event in terms of violence against a member of Congress.

For the most part, lawmakers are simply not a high profile target.  The last time a member of Congress was shot on American soil was 1968.  Since then, at least four federal judges have been gunned down.

Looking at historical records, I could find records of only four lawmakers for the U.S. House and Senate who have been assassinated, two of whom had very famous names:
 
Leo Ryan, the California Democrat who was gunned down on the tarmac in the 1978 Jonestown Massacre in Guyana
Senator Bobby Kennedy, killed by Sirhan Sirhan in June of 1968 after winning the California Primary
Senator Huey Long, who was shot and killed in the Louisiana state Capitol in 1935
Rep. James Hinds of Arkansas, killed during Reconstruction by a member of the Ku Klux Klan

If you really want to identify the group that has represented the most violent threat to members of Congress, it is lawmakers themselves, as ten members have committed suicide in Congressional history.

One lawmaker even took his own life in his office in 1933, Rep. Samuel Kendall of Pennsylvania, in what is now known as the Cannon House Office Building.

What is the biggest killer of members of Congress, other than natural causes?  That's easy.  Airplane crashes, followed by automobile accidents.

17 members of the House and Senate have lost their lives in plane crashes, the first in 1929.
 
Another dozen have been killed in car wrecks, the first in 1912.

Most of the time, lawmakers who die in office are claimed by natural causes, some kind of illness.
 
It's one reason the Saturday rampage had many worried in the Congressional Community, where tough words are part of the political landscape, but violence usually is not.

Before Nine Eleven, security could be somewhat lax on Capitol Hill.  

Now when there are votes, there are police officers armed with assault weapons standing out on the Capitol plaza.

As I always say, it's interesting going through the lunch line in the Capitol, when the AR-15 assault rifle slung over the back of the officer in front of you keeps poking you in the gut while he's ordering food.

25 years ago, there was talk of putting up a fence around the Capitol, much like the one which now encircles the White House, in order to bolster security for lawmakers.  

I'm actually surprised that it hasn't happened yet.