On Monday night's edition of "The Rachel Maddow Show," host Rachel Maddow discussed the fact that mass shootings are becoming more and more common in the U.S. over the last several years. She laid out a timeline of shooting incidents where more than 12 people were killed and showed that such incidents are becoming more and more a part of American life.

Maddow began by telling the story of the Camden Walk of Death, an incident that took place on September 6, 1949, in which a 28-year-old man walked out of his house and began shooting every person he saw, killing 13 people. It is the earliest recorded incident in a list of the 12 worst gun massacres in U.S. history.

If one looks at a timeline of the incidents listed in the Washington Post's list of the 12 deadliest U.S. shooting incidents, Maddow said, you will notice that the first six attacks took place over the course of 50 years, whereas the six most recent have all taken place within the last six years.

"The first half of this awful list happens across half a century," she said. "The other half-dozen of the worst killings in our history takes only half a dozen years until today. From Virginia Tech to the Navy Yard. The bloodshed of half a century is compressed into this blink of time."

She went on to say that if you as a citizen of the U.S. have been hoping that the massacres at Newtown and Columbine would spur the government into action on gun regulations and programs for the mentally ill, "you're still waiting."

"If you have been thinking that we live in an era that is more marked by this type of mass bloodshed than any era before," she concluded, "I am sad to tell you you are right. It did not used to be this way. But, more and more, this is part of how we live."

Watch the video, embedded below via MSNBC:

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