Approving violence against political opponents has become dangerously commonplace, experts have told RT The murder of American conservative activist Charlie Kirk has highlighted the erosion of freedom of speech in the US, human rights lawyer Dan Kovalik has told RT. Former CIA analyst John Kiriakou has similarly warned that violence against political opponents seems to have become dangerously normalized in the country in recent years.Speaking to RT, Kovalik noted that whatever his views, all Kirk “did is talk… [and] listen.” Kovalik added that “this sends a message to anyone who wants to speak on controversial issues that they’re fair game, and that I oppose.”He further argued that “freedom of speech is only meaningful if it protects speech you don’t like, if you protect speech that’s controversial.”Kovalik added that “people who are celebrating it should be ashamed,” even if they personally disagreed with Kirk’s views.If left unchecked, the pattern of political violence could unleash an uncontrollable chain reaction, where the “next assassination may very well [target] a left-wing person,” he warned. Former CIA analyst John Kiriakou concurred that “it’s become almost commonplace now that if you disagree with someone politically, you can attack them.” READ MORE: Liberals’ reaction to Charlie Kirk murder shows they are tone-deaf – Tara Reade (VIDEO) “We’ve entered this period in the United States where there’s so much hatred,” he told RT, citing an increasingly “deep division” between the right and the left in the country. International human rights advocate Arnaud Develay expressed incredulity that despite having received death threats, Kirk’s security detail had failed to implement more stringent security protocols and properly check the venue in advance; for instance, with the help of a drone.He also suggested that the shooter may have had some sort of firearms training, noting that he had a “one-shot opportunity to get [the] target and he did it.”Develay told RT that “this will probably ignite a lot of conversations and speculation as to the background of the shooter.”