"Those who does not decide (punish/rule/judge) according to my given kitab are Kaffir"- Al Qur'an: Maidah:44.
Most of the muslim countries are ruled according to their own constitution denying Qur'an. So according to the speech of Allah are the rulers Kaffir, and we who are accepting their rules?
"Only those who belief in Allah and His prophet, never confuses about it and struggle (Jehad) in the path of Allah are actual Momen." Surah Hujrat: 15.
None of us are not struggling in the path of Allah. Aren't we Momen? Then will we go to Hell?