Since Cruz is a Constitutionist and believes in state sovereignty, he will most likely propose that it should be the states that decide the Muslim immigration issue.
That would not work. A state does not want them but a neighboring state does. The states can not keep them within that state and they are free to roam.
I believe in state sovereignty also but immigration is legally a job for the Federal govt with input from the states. The states already have the right to inspect any refugees and they can reject anybody they believe is a threat to the state or will not fit in properly.