By now, I think everyone recognizes and admits this. Nine hundred years ago the response was to mount a string of disastrous and very un-Christian crusades. A political solution would be for churches to lobby the government to close down Muslim immigration, and make mosques illegal. We also believe in one God, but we define God as love. Love respects and cares for the freedom of others.
Love allows humans to try out other ways.
But love also invites comparison. To my mind that requires studying and comparing the explanatory models of religion. Departments of religion in our universities are right to point out there is no way to construct a single model for the rich complexity of a religion like Hinduism or Mahayana Buddhism, or even for Islam. But it is possible by questioning to construct an explanatory model for a particular individual's personal faith. And good models have an inner consistency and implications for how we live our life.