But still the Prussian Government was driven towards imperialistic expansion by the ever-increasing force of public opinion and popular discontent. It could only purchase renewed leases of autocratic power at home, with its perquisites for those who wielded and supported autocracy, by feeding the minds of the people with diplomatic triumphs and their bodies with new markets for commercial and industrial expansion; and the incidents of military domination grew ever more irksome to the populace. The middle classes were fairly content, and the parties which represented them in the Reichstag offered no real opposition to Prussian ideas of government. But the Social Democrats were more radical in their principles and were regarded by Prussian statesmen as open enemies of the Prussian State. Rather than submit to social democracy Prussians avowed their intention of making war, and war abroad would serve their turn a great deal better than civil strife. The hour was rapidly advancing two years before the war broke out. The German rebuff over Agadir in 1911 was followed by a general election in 1912 at which the Social Democrats polled nearly a third of the votes and secured by far the largest representation of any party in the Reichstag. In 1913, after a particularly violent expression of militarism called "the Zabern incident," the Reichstag summoned up courage for the first time in its history to pass a vote of censure on the Government. The ground was slipping from under the feet of Prussian militarism; it must either fortify its position by fresh victories or take the risk of revolution. It preferred the chances of European war, and found in the Serbian incident a means of provoking a war the blame for which could be laid at others' doors.