They need not convert to anything. All they need to do is declare themselves as 'secular' and have one-law, gender equality and uniform civil code. Once you declare a State as Islamic or for that matter any other religion, you kill the brain of people and live on the manipulation of clerics and waste time looking for answers in so-called holy books which you have been cleverly programmed to be the revelation of God and cannot be questioned, changed or challenged. And such things make people mad, mediocre and murderous as they forget the use of their own intelligence to excel in life, cultivate knowledge and skills, and seek solutions to real problems that always happen in day to day life by using science, technology, art, music, change, communication, questioning, research, development, sports etc. At the end of the day, our efforts are directed towards towards doing things that keep the human body and mind in the best of health and spirits and that requires us to be productive and occupied based on our education, economics, effectiveness and efficiency to maintain peace. That's why all developed countries are secular and excel in life, work, sports, performance and productivity.