There is little doubt that statement 2 will open the paragraph. The sentence says that democracy and high levels of inequality are simple incompatible. Why? Because very rich people will always use money to maintain their political and economic power.Thus 2 and 4 form a pair. Statement 1 says that now apart from the rich people we have another group: the unwitting enablers. What they do is described in sentence 3. Thus 2413 is the right sequence.