Asalaam-o-Alaikum
There are many things that can be done. First and foremost, we should forgive them and remember that they are jahil (ignorant). Many of these protesters are otherwise very decent human beings and are simply emotional and misinformed about the beautiful deen of Islam. The next thing that we should do is to make dua for them. When the Holy Prophet (s.a.w.a.) was attacked both verbally and physically, he prayed for his oppressors. Call to mind the incident at the city of Ta'if:
One time, Prophet Muhammad (s.a.w.a.) and his companion, Zayd ibn Harithah (r.a.) traveled to the city of Ta'if to preach the message of Islam. They preached that there is only one God and that the idols that the people worshiped were nothing but clay and stone; they had no power of their own. The people of Ta'if, however, did not wish to hear this. They, and their children, stoned the Holy Prophet (s.a.w.a.) and Zayd ibn Harithah (r.a.) day after day. After suffering an immense amount at their hands, the Angel Gabriel (a.s.) descended to Muhammad (s.a.w.a.) and said "give me one word, and I will flip these houses and kill all that reside inside!" Muhammad (s.a.w.a.) replied, "No! Despite all that they have done to me, I'm going to just let it go, and I pray that one day this city will breed some sweet believing souls." (Note: I wrote this from memory. The quotes are not exact.)
In addition to praying for these people, we should return their insults with kindness. I heard (although I haven't confirmed) that a group of Muslims in the UK prepared tea and biscuits for a group of protesters that were protesting outside of a masjid. They even offered the protestors to come and play football (soccer) with them. This is one way that kindness can be shown, although it doesn't have to be this extreme.
The kindness you show should indeed extend beyond the protestors and include everybody in your community. One time a Muslim payed for my Christian mothers groceries at the store even though he had no idea who she was, nor did he know that her son is a Muslim. This was an extreme act of kindness and it came at a very unique time because my mother was struggling financially and due to this act of kindness, she could now afford to fill the car with gasoline. You never know when a random act of kindness can truly affect somebody's life.
Additionally, we should organize more events to show how peaceful and tolerant true Muslims are. In my first paragraph, I mentioned that most of these protesters are ignorant of Islam and believe it to be a violent ideology. We need to show them otherwise. The masajid in my area often have various interfaith programs where they invite a Christian Pastor or a Jewish Rabi to speak at the masjid and they send a Shaykh to speak at a Church or Synagogue. One masjid in particular in this area hosts short conferences about the life of Prophet Muhammad (s.a.w.a) as well as seminars on important days. For example, they held a seminar about peace and diversity on Martin Luther King Jr. Day this last Monday. The Ahmadiyya Muslim Community hosts an annual blood drive (known as "Muslims for Life") around the time of 9/11 and each year they are able to raise enough blood to save the lives of many times the amount of people that were killed in the September 11th attacks. Events such as these can go a long way in showing that Islam is nothing to fear and that we are a peaceful bunch of people.
Finally, if all other options are exhausted and you are still being harassed, especially if you feel that your life, your family, your property, is your well being is in jeopardy, the best thing to do is to contact the police. If they will do nothing, keep documenting everything. Take notes on all of the incidents of harassment. Take photographs. Record as much information as you can and then go to the police with this. If they still are able to do nothing, go to a higher agency.
InshaAllah the hatred and ignorance shown towards Muslims will come to an end soon. Ameen.
Wa alaykom salaam.
