It is not as simple.
Generally speaking no liberal does support the Muslims that are regressive and far-right conservative.
Now the recent issues though show IMHO why you may think Muslims get “positive discrimination” lets look at the Syrian Refugees and Iraqis and Afghans that helped Americans waiting for permission to come to the USA; I noticed a typical case that recently had a family from Syria move to Arizona, they came to the USA because they actually did accept democracy and wanted to make Syria more secular so they did protest against Asad in Syria during the Arab Spring.
Their home was destroyed in the bombings ordered by Asad, they did stay in a Syrian Refugee camp in Jordan for years, until they were given the chance to come to the USA.
They were lucky to come before the xenophobia was turned up to 11 by the conservatives. The point here is that there are Muslims that risked their lives for ideals that are precisely in the mold that you are demanding for, but they are being blocked by irrational fears, fueled by xenophobia too.
I think that guys like Trump and most Republicans are doing a really dangerous move that does affect our troops overseas by making very ignorant statements about not vetting properly the few refugees that the USA does accept.
Because IMHO many Iraqis and Afghans that risked their lives by giving support or even intelligence to the American troops are having their lives endangered thanks to delays that prevent them to come into the USA, thanks to the absolutism shown by the conservatives.
I do think that people of many nations that have sympathies for the USA and their ideals will think more than twice than to offer any help to Americans, or to oppose dangerous dictators, when they see how many that did risk their lives for democratic ideals are denied lifelines.