Is it permissible to elect a president for an Islamic country who does not rule by God's law, if not electing him could lead to harassment and arrests?

Believers firmly hold that no one's judgment is better than Allah's, and any judgment that contradicts it is jahiliyya (ignorance). Allah Almighty marvels at those who claim to believe in Him and what He has revealed, yet desire to seek judgment from Taghut (false deities/tyrants). Allah has sworn that no one truly believes until they make the Messenger (peace be upon him) a judge in all matters and submit completely to his judgment. Allah has made it obligatory to refer disputed matters back to Him and to the Messenger as a condition for faith. Accordingly, it is forbidden to elect anyone who governs by other than Allah's law, as this implies approval of and assistance in a forbidden act. If a Muslim is compelled to go to the polls, he can reject the president or spoil his vote if he is able. If he cannot but agree and fears harm, then there is no blame upon him, based on the words of Allah Almighty: "Except for him who is compelled [to renounce his religion] while his heart is at peace with faith" (Quran 16:106), and the words of the Prophet (peace be upon him): "Indeed, Allah has pardoned for my Ummah (nation) their mistakes, their forgetfulness, and what they are compelled to do."