The idea of sharia, or Islamic law, had become frightening in conservative circles, where right-wing outlets falsely asserted that Muslims were moving to Europe and setting up “no-go zones” in which police were banned and imams made the rules based on sharia. Their fear was that such a phenomenon would happen for real in America. - The Washington Post
I'm not worried about the influence of Islam on America.
What makes America more susceptible to fundamentalist brands of Islam than Muslim majority countries like Tunisia and Turkey, where there have been discussions about legalizing same-sex marriage? What makes the US more likely to pass Sharia Law than Muslim countries where homosexual relations between females is already legal like in Kuwait, Turkmenistan and Uzbekistan? Or Albania, Guinea-Bissau and Sierra Leone where they have signed a UN Declaration supporting LGBT rights? Or Albania, Kosovo, and the Turkish Republic of Northern Cyprus which provide LGBT rights protections in the form of anti-discrimination laws, and discussions on legally recognizing same-sex marriage have been held?
These are all Muslim countries.
Broad-brushing Islam doesn't lead to understanding of your neighbors, but rather leads to fear. Instead of fearing the negative, I'd rather support the positive. Life is more fun that way.
If you are concerned about what Islam teaches try this instead:
Financially support the Muslim schools that teach a more liberal version of Islam, like Zaytuna College in Berkeley. They are making great strides in stemming the ignorance that exists within their own faith.
Make friends with your Muslim neighbors so they won't just exist in an echo chamber, in case they do and are being influenced by Salafist rhetoric.
Buy a more gas efficient car or use your bike instead so you won't be supporting the people who are spreading fundamentalist Islam around the globe - the Royal House of Saud (Saudi Arabia). Every time you fill up your gas tank you're helping some Salafist or Wahhabi imam preach his ignorance.
Support Congressmen and presidents who don't support the status quo of American foreign policy which has been proven to destabilize Muslim countries leading to an increase in Political Islam, hatred against the US, terrorism, death and trauma to American soldiers, and attempts to create a caliphate which has no respect for majority Muslim opinion. Your choices within the major parties are very limited in this regard. Consider other parties.
Oppose our government financially supporting and arming "freedom fighters" who are fighting against Syria's government. They are branches of al-Qaeda and ISIS. Even if we do succeed in regime change in Syria we will be fighting for decades against people who will be shooting at us with the weapons we have supplied to them. I'd be more worried about that than the poor Syrian refugee family coming to American who got his city destroyed just so we don't let Russia get access to their oil.
When we point a finger at Islam we are pointing 3 fingers back at us. Instead of worrying about the House of Islam we need to clean our own house first. Islam is not our enemy. If you want to see our enemy, look in the mirror. We cause our own problems.
If we really want to Make America Great Again in the eyes of the rest of the world we need to own up to what the rest of the world sees us as: a country hell-bent on stirring up a bee's nest to get at the honey before some other bear, like Russia gets to it. Instead of trying to control the world's supply of oil to guarantee our own supplies we should learn to live on what we can produce for ourselves. It is true that we are on target to become a net oil exporting country by 2027, but the more we reduce our own consumption the more we can supply other countries like China so they won't have to get it from Saudi Arabia.
So Russia wants to be chummy with Syria's president so they can be his prime oil customer. Big deal. Let them have it and let them deal with the radicals we've been propping up which magnifies this conflict. If we had let Syria and Russia deal with insurgents without our interference we wouldn't have this huge Syrian refugee crisis to begin with.