But the're not white terrorists, which makes the Muslims responsible for all terrorism. Be afraid!
The point with the concern, concerning Islamic extremism was that Muslims form only 2% (just over) of the population.
With 2% of the population you would then expect 2% of the crime in any given area, whether murder or theft etc. Crime should be proportional to population size.
So in a nation with 70% whites you'd expect the largest proportion of any area of crime to come from this group, since they account for 70% of the population. So, just like above you would expect 70% of all murder, theft, rape incidents etc. to come from this group.
Seeing population size and crime can also help you address issues in certain communities: for instance if a group garnering 17% of the total population is responsible for 50% of all theft, burglary etc. and 70% of all welfare subsidies (just random numbers here) then we could address this community with more education opportunities, a higher quality of education, and assistance with employment etc. so knowing various demographics and their statistics is a helpful tool..
I once went back and counted all terror attacks listed by government agencies from the 1980's to a few years ago and categorized them according to demographic and found that terror attacks from the larger Muslim community (perpetrated by Muslims or those from Muslim majority nations originally) constituted over 35% of all attacks. (If memory serves me correctly but even if you give me a large margin of error, its still serious)
That, from a group that consists of only 2% of the population is concerning.. as it's extremely disproportionate to population size..
This screams there is a problem within this community. And, as the population size increases if terror attacks from this demographic stay at these disproportionate numbers we WILL have a serious problem and by then it may be too late to solve it.
So in short, no, so long as right wing political terror attacks happen in accordance with population size (or lower) it's not as concerning because there is always going to be, within any demographic, a percentage of the population which is mentally unstable.
I have been happy to see the decrease in terror attacks by Muslims, however. hopefully we can keep this up for the next few decades.
*** I no longer, that I know of, have my work on that research as I was on a different computer back then and likely didn't save it and if I did I don't imagine I know where. I did that research years ago and I'm sorry for that. But anyone looking into it will find the same - just a little leg work.