First I believe the practice of polygamy was inspired during the difficult trek across the Plains where several widows needed to be sheltered and provided for. When the Saints arrived in the Salt Lake Valley and Utah the practice of polygamy was not as critical for the safety and security of the church. That being said well before the debate about statehood the Prophet Joseph Smith received the 12 Articles of Faith that requires the members of the church to obey, honor, and sustain the law. So the answer that Wilford Woodruff received was also inline with the earlier revelation and we see that God is the same today as he is yesterday as he will be tomorrow. If the lord needs the members to practice polygamy again he will provide a way.