For the US, this is why: https://gist.ly/youtube-summarizer/islamization-of-america-the-rise-of-muslim-communities https://www.datapandas.org/ranking/muslim-population-by-state https://en.wikipedia.org/wiki/List_of_mosques_in_the_United_States#Growth_in_the_21st_century
For my country Germany it's way worse:
As of 2025, there are approximately 5.5 million Muslims in Germany, which accounts for about 6.6% of the total population. About 3 million of them are German citizens.