As the debate continued, Wilhelm became more and more interested in social problems, especially the treatment of mine workers who went on strike in 1889. He routinely interrupted Bismarck in Council to make clear where he stood on social policy; Bismarck, in turn, sharply disagreed with Wilhelm's policy and worked to circumvent it. Bismarck, feeling pressured and unappreciated by the young Emperor and undermined by his ambitious advisors, refused to sign a proclamation regarding the protection of workers along with Wilhelm, as was required by the German Constitution.