Update (at bottom): Pro-gun ads appearing in this report not directly linked to RAW STORY

The date April 19 seems to have a strange echo in American history.

According to the media, a pro-gun group planning a rally in Washington, D.C. on that day is doing so because it is the anniversary of the Oklahoma City bombing. While technically correct, that's not half the story.

The controversy surrounds two groups: Oath Keepers and Second Amendment March; one, a rapidly growing association of current and former military and law enforcement personnel who've sworn an oath to uphold the constitution, even if ordered otherwise; and the other, a pro-gun group organizing rallies across the country.

While Oath Keepers forbids its members from ever ushering U.S. citizens into a military tribunal or a detention camp, its promotional materials tend to focus on resisting the Obama administration -- even though their items of concern are artifacts from the Bush administration. They were the subject of a recent profile in Mother Jones magazine, which characterized them as deeply resentful of President Obama.

Even as they damn the Democratic administration for wanting to take their guns, it was President Obama who made open carry of firearms in national parks legal again. The National Rifle Association seemed pleased by the reforms, but instead of being thankful for the president's signature, they congratulated Republican Senators for the achievement. The law took effect on Feb. 22 of this year.

In an ironic twist, one of the groups plans to hold their open carry rally on national park land, though the caveat will likely be lost on most participants.

In a video promoting the group's fundraising efforts (under the term "money bomb," first coined by the Ron Paul campaign), a narrator claims that the 2008 election was "a wake up call" for Americans, and the footage showcases tea party rallies set to epic music.

Of course, they had to pick April 19 for their rally. Not only is it the same day as the Second Amendment march, it is the anniversary of the Oklahoma City federal building bombing.

However, it is also the anniversary of the Waco Branch Davidian massacre ; an event which inspired Oklahoma bomber Timothy McVeigh's brash and violent act of terrorism. This little discussed fact was explored by American iconoclastic writer and historian Gore Vidal in a feature for Vanity Fair, published in 2001.

A third significant event in American history took place on April 19, one which Oath Keepers claims to be honoring with their rally date. According to the Library of Congress:

On April 19, 1775, British and American soldiers exchanged fire in the Massachusetts towns of Lexington and Concord. On the night of April 18, the royal governor of Massachusetts, General Thomas Gage, commanded by King George III to suppress the rebellious Americans, had ordered 700 British soldiers, under Lieutenant Colonel Francis Smith and Marine Major John Pitcairn, to seize the colonists' military stores in Concord, some 20 miles west of Boston.

MSNBC's Rachel Maddow noted the date and noted that the groups claim they are not honoring McVeigh, yet reiterated that April 19 had become known "in recent memory" as the Oklahoma City anniversary.

The Oath Keepers' Web site seethed with venom over her reporting.

"Apparently Rachel Maddow only respects the Bill of Rights when leftists are using it," wrote Stewart Rhodes, the group's founder. "When those she hates (anyone she considers to be on the political right) want to simply exercise their constitutionally protected freedom of speech, assembly, and also their constitutionally protected individual right to keep and bear arms (while in full compliance with current Virginia laws), she screeches so loud you’d think they were going to conduct human sacrifices.

"And God forbid you ever do anything on April 19! According to Rachel Maddow, because the Oklahoma City bombing in 1995 was on that date, you can no longer dare to meet or congregate on April 19 to celebrate your heritage or to honor those who fought for liberty back on April 19, 1775, or to do anything else, lest she and her fellow travelers equate you with Timothy McVeigh."

"A political climate that's already more overheated than any time in a generation. Plans for a large-scale rally of firearms enthusiasts in the nation's capital," wrote Will Bunch at Philly.com. "A fast-growing group of (mostly ex-) military and cops that pledges to disobey 'unconstitutional orders' from the president, and an 'urgent' call from the group's leader to flood Washington to 'shout your oaths in the tyrant’s face' -- on the 15th anniversary of the worst home-grown terror incident in U.S. history, the Oklahoma City bombing.

"What could possibly go wrong?"

"Unfortunately, though they tried to get famous rock star and gun lover Ted Nugent to speak, organizers have lamented on their Web site that they couldn't afford to pay for Mr. Nugent," Maddow concluded. "So, no Ted Nugent, but a member of Congress will be there."

This video is from The Rachel Maddow Show, published to YouTube on March 31, 2010.

Update: In a second stroke of irony, some readers may have seen the following advertisement just below the portion of RAW STORY's report that describes how President Obama has expanded gun rights:

An alternate version of the ad featured President Obama's bust above a pile of firearms with the bold letters "GUN BAN" hovering over his shoulder.

The image, placed by Google AdSense, tied to keywords in RAW STORY's report, making the marriage of our content and their advocacy possible. RAW STORY in no way endorses this group's message. Their ad linked to a page hosted by the National Association for Gun Rights, featuring Rep. Paul Broun (R-GA), the only member of Congress who has announced plans to attend the April 19 pro-gun rallies in Washington, D.C.

The Georgia Republican is guilty of numerous hair-raising exaggerations in his rhetoric, including a claim that Democratic leadership intends to declare martial law in the United States and establish a totalitarian state under their sole authority, which would be ushered in by a pandemic or natural disaster.

He also believes President Obama has established a private army at his personal command, has usurped complete control of the American media and is in the final stages of making guns illegal. Broun was also an enthusiastic supporter of the Republican meme that making health care available as a public service would result in mass casualties