Is it permissible to emigrate to Europe for work and self-development then return to the homeland, or do difficult living conditions not justify emigration to infidel lands?

Traveling to non-Muslim countries poses a great danger to one's religion and morals, due to the freedoms prevalent there and the lack of denunciation of evil. The Prophet, peace and blessings be upon him, disavowed "every Muslim who resides among polytheists, such that their fires are not visible to each other." However, if the traveler is a person of knowledge and insight, and his journey is for the purpose of inviting people to Allah and clarifying the virtues of Islam, then it is permissible for him to do so, provided that he is safe from falling into what Allah has forbidden. This is very difficult, especially for an unmarried young man.