The Islamic State’s affiliate in Egypt is on the march. On Palm Sunday, a pair of bombs killed 45 people at church. This was the third major attack on Coptic churches in less than four months — and the first such attack recently in major Egyptian cities, which many people believed were more secure. These attacks follow after months of terrorism, and they could have been predicted: Just two months ago, the Sinai-based Islamic State affiliate issued a video promising that the group would target Copts in Egypt’s mainland.

These attacks demonstrate that President Abdel Fattah el-Sisi’s counterterrorism strategy is failing. Mr. Sisi claims that he is committed to fighting terrorism, but in reality his energy is directed toward his other enemies: secular activists, journalists, independent members of Parliament, businessmen and academics who oppose him, human rights organizations and peaceful dissident Islamist groups.

In response to Sunday’s bombings, Mr. Sisi declared a three-month-long state of emergency. North Sinai province has been under emergency law since October 2014. But the deterioration in the security situation there over the past year is a reminder of how such policies fail. The fact of the matter is that the national emergency law will do little beyond giving legal cover to the brutal practices that have already been enforced for the past few years in flagrant violation of Egypt’s Constitution. (After all, Mr. Sisi has previously stated that the Constitution was written with “naïve intentions.”)

North Sinai looks increasingly like Mosul, which until recently was the Islamic State’s de facto capital in Iraq. Earlier this year, Egyptian news media was full of images of desperate Christians being forced from their homes in Sinai by Islamic State militants in a scene reminiscent of the jihadist group’s takeover of Mosul in 2014. In al-Arish, North Sinai’s capital, the Islamic State has reportedly set up checkpoints to force female public servants to adhere to a strict Islamic dress code. Young men have reportedly been flogged in public squares for the “crime” of selling cigarettes.