Sorry, fstar. That's not how it works. You made a claim. The burden is not on me to disprove it, but for you to prove it. That requires you to provide evidence not only that there is violence from the political left (which no one has disputed) but also that it exceeds the violence on the right. Furthermore, just because the parties switched sides does not mean that the left and the right only came into existence during and after that re-alignment. So, unless you are indeed moving the goalposts, you will also have to prove that it has always been that way, as you initially claimed.
Once you have provided this data, I will respond. Until then, it is is a baseless claim, which does not require nor deserve substantive countering data from me. If you are unable to support your claim with evidence, I don't need to do anything but point out that failure.