You cannot be secular toward an unsecular religion like islam. Islam is a religion that believes all other religions are corrupt and inferior. And the quran urges muslims to kill kafirs. So I do not see any reason to be secular towards an unsecular religion like islam. There is no secularity for non muslims in muslim nations so why expect it to work the other way?
In addition Taslima has the freedom to express herself. Is islam is a monstrous religion, she should have the right to freely express her views. Muslims have sensored out any opposition to their religion by killing anyone who speaks out against islam, and we need to draw a line and let them know that non islamic countries like india will not allow this nonsense.