geoff you do ask important questions and their answers are historically deep.. however I must simply give the answer..
politics and religion are two very good friends from the begining of history.. and they both use each other in every opportunity..

now , in order to analyse the situtation we must be aware of some facts..
* many politicians in order to have more power, abuse religion everytime even if thats a republic or a kingdom.. as it means millions of votes..
* religion by its nature is very prone to abuse as its originally a series of god given laws to arrange human life..
so saying to be secular or trying to be secular in real terms has no meaning imo.. as an experience I can say including many western countries and middle east countries secularity is nothing more than a talk or something only on paper.. there are millions of examples which prooves that a country saying secular in reality is not..
actually religion is the one which is mostly the winner..

now other facts:
* especially in middle east countries religion is a serious means of earning money.. if you start to demonstrate
yourself a religious person you will have many people around you helping in every possible way..
* now if you have ever had the chance of reading those books especially the one you mentioned
you will see that it has some sayings that can seriously start a war.. However after two thousand years anybody
who accepts those statements serious and acct accordingly must be handled seperately from community imo..
* however adding to the complexity of problem some west and some developed middle east countries
obviously pump more fuel to the fire.. you can guess who they are..
now explaining my position , I do believe neither of those books.. they are from the past, may be valid in their day
and some of their rules may apply to this day but actually cant help manage my life in this century..
now about the subject of burning those books.. nope.. wont help solve nothing..instead will start a big fight between
the believers of those religions and western world.. and bring ultra trouble..
and a final fact:
* I think some western countries must stop helping those religious fundemantalists (also here) or
they will get many copies of iran in middle east..