I believe they both are. Islam is a militaristic religion whose true believers seek expansion through military conquest of the globe. We can all accept that.
I do not since I know Muslims with no interest in doing anything like this.
However white people seem to have this innate tendency regardless of religion whether it was the atheist USSR expanding communism, the neo-pagan Nazis or the Christian Spanish conquest of the Americas.
It is a human trait not a specific. China throughout history face repeated invasion from civilizations that are far more militaristic in nature due to be nomadics than from an rural heavy civilization.
Christianity is a more pacifist religion yet the supposedly Christian Europeans conquered much of the world after the 1600s in a violent way.
Christianity was tamed due to the violence it's own organizations created and imposed upon it's own and foreign populations due to just such events. Before these events Christianity faced an expanding Muslim Empire in Spain and in Asia Minor/Balkan. The only reason Christianity is highlighted is that it was the latest in history.
And it didn't stop with colonialism. Within Europe, the two world wars were the most destructive events of modern history.
Destruction increases due to technology. However World War 2 was not solely the product of Europe as Japan is not European. The European theater barely went beyond North Africa, the Urals and the Atlantic while the Asia Theater covered China, Eastern India, and all of South-West Asia. Japan started it's war years before Germany did anything. It only started to include colonial powers when said powers had their power broken at home.
After WW2, with the atom bomb the white man stopped fighting each other. Instead they carried on fighting through third world proxies.
China was no one's proxy as evident from it's split from the Russia Soviet system. Proxies are not new nor unique. Many powers throughout history used proxies to weaken an enemy
I would agree that Islam is a threat to world peace but also that Europeans are also a threat to world peace. The current chaos in Iraq started after the west invaded.
It started when the West turned a blind eye to a dictator and supported him only to see him turn against them. However the sectarian violence from Iraq was already present within the society due to the culture and religion of the area. The West didn't force Shia nor Sunni to start fighting each other. That mentality already existed.