A few counterpoints.
First, this is nothing new. Islamic states have done this since the Umayyad Caliphate.
Second, late medieval Christian states that allowed Muslims to remain, and to stay unconverted, had burdens of their own.
Third, and per the last part of the post?
Not to go too much Gnu Atheist, but tax deductions for religious groups, from state sales and property tax ones to all religious contributions, not just for their actual charitable work, being deductible from federal income taxes, could be considered a tax of sorts on secularists, could it not?
Survey says ... yes.
You can Google elsewhere for the totals, or I can tell you that it's $71 billion with a b in religious tax deductions per year.
And, while, theoretically, making that up elsewhere falls on us all, it really falls on secularists who are almost as small a minority in the US as Christians are in Iraq.
"The issue of religious tax preferment is especially relevant now because the number of Americans living outside any religious tradition continues to grow," said Tom Flynn, Free Inquiry's editor. "That underscores the unfairness of taxing all Americans to subsidize religious institutions that only some Americans utilize."
The most ridiculous part of that money is the $41 billion for capital gains exemptions.
Also, given the way the Catholic Church has worked to shelter its assets behind various walls, including tax-related ones, to try to avoid paying out money in sexual abuse lawsuits, besides dinging us secularists, there's a fair chunk of ethics issues involved.
So, secularlists? Convert, or pay the tax that's not being paid by the religious.
Of course, as this ginned-up lawsuit over bald eagle feathers shows, wingnuts within Christianity always believe the First Amendment doesn't really apply to them.