Firstly, it is important to understand that what is made unlawful for us is dealing in interest by taking it, giving it, writing it or witnessing it ourselves. As for others in the society, we can only advise them. Even in the state of Tawheed i.e. Madeenah in the time of the Messenger of Allaah (peace and blessings of Allaah be upon him) there were jews living their who use to deal in interest and the Messenger of Allaah (peace and blessings of Allaah be upon him) himself use to buy things from them.
Secondly, it is still not permissible for a Muslim to live in a society whose monitory dealing is totally based on interest, without there being a compulsion. However we are not aware of any "non-nterest based economy" that exist on earth these days.
And if there is no such place available then the principle for a Muslim is in what Allaah Subhanahu-wa-Ta’alaa says:
16. So keep your duty to Allâh and fear Him to the best of your ability; listen and obey, and spend in charity; that is better for yourselves. And whosoever is saved from his own greed, then they are the successful ones..At-Taghabun.
And Allah the Most Knowledgeable knows what is best and most correct.
We ask Allaah to help and guide us to do all that He is pleased with and his Peace and blessings be upon His last Prophet Muhammad
