R&S ATHEISTS: Why can't some 'christians' understand the simple difference between the statement, "I don't?

believe in 'god'," and the statement, "I believe there is no 'god'?" When an atheist takes the second position, they deserve no mercy. They have opened themselves to legitimate criticism, because it is impossible to know with 100% certainty that no 'god' exists. However, the simple statement, "I don't believe in 'god'," is totally defensible, because it doesn't presume knowledge no one can have. So, why can't 'christians' understand that when they misquote the basic stance of atheism, "I don't believe in 'god'," as one of the 'christian' heroes, Ravi Zacharias' does, they are the ones who manage to paste the 'STUPID' card to their foreheads?