Nathan Kalmoe published a paper on Sept. 15, 2010 that indicates it does.
Abstract
Does violent political rhetoric fuel support for political violence?
Political leaders regularly infuse communication with metaphors of fighting and war. Building from theoretical foundations in media violence research, I field a nationally-representative survey experiment in which subjects are randomly assigned to different forms of the same political advertisements. I find that even mild violent language increases support for political violence among citizens with aggressive predispositions, especially among young adults. please read the paper before you state your expert opinion.
http://docs.google.com/viewer?a=v&q=cache:Fkhx1XcI1QIJ:sitemaker.umich.edu/kalmoe/files/kalmoe_-_political_violence.pdf+nathan+kalmoe+political+rhetoric&hl=en&gl=us&pid=bl&srcid=ADGEESiwDAG3I-6UOJ7O83AGLLpTUkZ8xxjSzxi5-lY715OQVijprj7i4VYT7Jxd0tUFL-V525jazULAEKPbtYfdi5mCWBlXbgnwrBFrI0w1MC8QEffy4Hu1YvtmdMVE_Nu08EQ6Pe2s&sig=AHIEtbQbgFJMh6CKqZdYuMz7LRRNbm3Utgit's very timely
The specter of political violence haunts even the most stable democracies, including the
United States. Assassins have shot down American Presidents, members of Congress, federal
judges, state governors, mayors, activists, and others. Political extremists have exploded bombs
outside government buildings. Vandals have smashed and ransacked government offices. And
each year, the Federal Bureau of Investigation, Capitol Police, and the Secret Service respond to
hundreds of threats made against public officials and their families.
Recently, the furor surrounding the national healthcare debate – beginning with raucous
town hall meetings in August 2009 and culminating in the bill’s passage in March 2010 – led to a
spike in death threats against public officials and smashed windows in Congressional offices;
someone even cut the gas line at a house thought to belong to a Congressman after the wrong
address was posted on a hostile website (Hulse 3/25/10). Another man wrote an anti-government
suicide note before flying a small plane into a Texas IRS building, killing himself and one
employee (Brick 2/18/10).
As protestors marched outside the U.S. Capitol building chanting “kill the bill” – some
carrying signs with slogans endorsing explicit violence – political leaders inside and others on
television literally shouted their opposition as they described apocalyptic implications of
passage. Congress members appeared regularly before the crowd, showing their approval by
waving their own “kill the bill” signs and a “don’t tread on me” flag (Hulse 3/21/2010). One
leader posted a map on Facebook with rifle cross-hairs on the districts of lawmakers who voted
for the bill, alongside their names (Palin 3/23/2010a), and later added a Twitter post saying,
“Don’t Retreat – Instead, RELOAD!” (Palin 3/23/2010b). At least four of the “targeted”
members of Congress received death threats or had their offices vandalized with bricks thrown
through their windows (Bazinet 3/24/2010; Rich 3/27/10; Rucker 3/25/2010). The governor of
Minnesota encouraged supporters to “take a 9-iron and smash the window out of big government
in this country,” (Condon 2/19/10). And in the early months of 2010, with the acrimony
surrounding the health care debate, the Senate Sergeant of Arms reported a 300-percent increase
in threats against members of Congress (Lovley 5/25/10). This conjunction of opposition
politicians encouraging hostile crowds and the outbreak of death threats and vandalism led some
commentators to ask whether political leaders were partly to blame for the violence and threats
(Rich 3/27/10).3
(from the introduction)