This time, international expressions of concern and calls for restraint will not suffice. The Egyptian military’s brutal clearance this morning of Muslim Brotherhood sit-ins in Cairo demands the same outrage that would follow if secular protesters were killed by an Islamist government.

Responding clearly -- and in the case of the U.S., freezing $1.5 billion in annual aid to Egypt -- isn’t solely a matter of principle. Reports of secularist civilians in Cairo attacking the Muslim Brotherhood protesters, and of possible Islamist retaliation against Christian churches in central Egypt, show that the military’s policies threaten civil war. An all-out sectarian war, with the military largely on one side and Islamists largely on the other, is in nobody’s interests.

Followers of the Muslim Brotherhood, who account for as much as 30 percent of Egypt’s population, must be convinced that they have some recourse other than armed insurgency. Obviously, such reassurance must come from secularists and democrats in Egypt. Mohamed Elbaradei, the former chief of the United Nations’ nuclear watchdog and a leading figure in the transitional government, sent an important message by resigning in protest over the killings.

The European Union, by contrast, expressed only “concern” and urged “restraint” in its response today. As the scale of the violence became clear, the White House rightly went further to “strongly condemn” the crackdown. Firmer and more explicit condemnations of the military’s brutality by the outside world can only help.

Today’s death toll remains unclear, but initial statements from Egyptian officials -- that no civilians were dying, that soldiers and policemen (some of them masked and carrying Kalashnikov rifles) used no live rounds -- were Orwellian. The health ministry later said 149 were dead. The Washington Post’s Cairo bureau chief posted on Twitter that police were firing live ammunition into the crowd. Although some protesters may have fired shots, and in recent weeks were accused of torturing opponents, the tactics of the security forces were clearly disproportionate. One video clip shows the charred remains of two people burned inside their tent.

Supporters of deposed President Mohamed Mursi have been unreasonable in their unwillingness to negotiate any solution to the crisis that doesn’t include his return to power. Mursi was dismissive of democratic processes when in power, and his return is neither possible nor, at this point, desirable. Still, the military’s claims that the opposition consists of terrorists are false. The risk is that, as occurred when President Bashar al-Assad made similar claims about protesters in Syria in 2011, the propaganda proves self-fulfilling.

The protesters’ complaint against the July 3 military coup was at least understandable, even for opponents of the Muslim Brotherhood’s goals and methods. Peacefully resolving this dispute over the coup required patience and diplomacy. Instead, the military resorted to arrests and escalating violence, no doubt encouraged by the mildness of the international response to each successive abuse. At least 130 pro-Mursi protesters have been killed in the last several weeks, and this morning’s assaults provided new martyrs for the Islamist cause, as well as an iconic injustice around which to rally. Think Northern Ireland’s Bloody Sunday in 1972.

Egypt’s brief experiment with democracy is probably over. What comes next is a question mostly for Egyptians, and it will very likely be something less: Today the military declared a monthlong state of emergency. Of the 46 years since 1967, Egypt has been under emergency rule for all but three, suggesting that the measure -- which includes the right to detain without trial -- won’t be lifted soon.

The U.S. and its European allies can and should press the military to end emergency rule. They should also suspend any aid programs to the government, in particular to the military. Egypt’s generals must be made to understand that the kind of brutality that took place today in Cairo has consequences.

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