The title is misleading. The rally was not comprised of only radical/extremist people and the purpose was not advocate for a caliphate in Germany. That's just click-bait. The rally was a response to the rise of anti-Islamic portrayal in media outlets following the conflict in Gaza and the German support of Israel. The article barely mentions this issue and focuses mainly on trying to prove that the protesters are indeed Islamic extremist. While there are indeed extremist tendencies from a number of participants the main issue is the denouncing of the media portraying "all Muslims in Germany as radical Islamists." However the article makes it seem as if Muslims are trying to take over part of the country or something like that. I could not find this story in mainstream media outlets, which I found weird. And most articles covering this story have similar click-baity headlines. Plus, the information cited comes from only one media site.