Every six months the Director of National Intelligence must report, by law, how many terrorists formerly detained at Guantanamo Bay have resumed terrorist activities. The last report pegged the recidivism rate at 30.1 percent —124 confirmed as once again engaged in terrorism, 96 suspected of it.

That report was issued on Jan. 15. The next should be published soon. As we brace for those new numbers, it may be useful to review some background information.

Since Sept. 11, 2001, the U.S. has detained more than 100,000 jihadis. Most were detained in the countries where they we captured, but some 780 were sent to Guantanamo Bay, Cuba. A few died there, most of them suicides. But 728 have now been released or transferred elsewhere — to countries ranging from the United Arab Emirates to Uruguay.

Today, only 40 terrorists remain at Gitmo. But they are considered the worst of the worst or, in the words of President Trump, “really bad dudes.” That is why we should all appreciate that Trump has kept his campaign promise to do the opposite of what President Barack Obama wanted to do: keep Guantanamo Bay open to detain these very dangerous terrorists. Trump signed an executive order to that effect on Jan. 30, 2018, reversing an Obama executive order issued in 2009 that tried to close the military prison.

Tragically, at least 220 of their released comrades in arms (that we know of) have resumed their former “really bad” activities. And keep in mind that the DNI has a very high standard for this report: It does not consider a Gitmo grad as a “confirmed” recidivist unless there is a “preponderance of evidence” or “reliable, verified, or well-corroborated intelligence reporting” that identifies a former Gitmo prisoner as directly involved in terrorism.

These recidivists include terrorists like Abdallah Saleh Ali Al-Ajmi, who was transferred by the Bush administration from Gitmo to Kuwait, which then released him. He subsequently drove a truck filled with 5,000 to 10,000 pounds of explosives onto an Iraqi army base, killing 13 soldiers and wounding 42 others in a 2008 suicide attack.

Another former Gitmo detainee is Ibrahim al Qosi. Transferred to Sudan by the Obama administration in 2012, al Qosi became a senior leader of al Qaeda in the Arabian Peninsula.

Clearly, a large number of detainees “graduating” from Gitmo should never have been released.

No, not everyone at Gitmo deserved to be there. Early in 2002, the Bush administration released some detainees because they were, in fact, not terrorists. These unfortunates had been caught up in the fog of war. It happens. And releasing them was the right thing to do.

Later, the Bush administration began transferring supposed “lower level” detainees on a case-by-case basis to their home countries or other countries, as long as those countries promised to mitigate the threat that those detainees posed.

After the lower level threats were transferred off the island, Bush, then Obama, continued to transfer more dangerous terrorists off the island, each with specific assurances from the receiving country that they would mitigate the threat.

It’s good to keep these facts in mind, as the Center for Constitutional Rights has filed a new legal challenge in federal court to free the remaining terrorists at Gitmo.

The recidivism data make one thing very clear: There never has been, nor will be, any risk-free transfer or release of Gitmo detainees. Year after year, more and more Gitmo grads show up on the DNI’s confirmed or suspected list. We will never know with exactitude just how many additional acts of terrorism they will commit and how many more innocents they will kill.

But we will know one thing for sure: None of those new acts of terrorism would have happened if those detainees had remained in Guantanamo Bay.

The repeat acts of terrorism by many of these former detainees show just how wrong organizations like Human Rights Watch have been. For years, they have strained to get all of the detainees transferred off the island, waging a propaganda war that paints these terrorists as innocent bystanders, the victims of a cruel and unfeeling U.S. government.

In truth, however, those still stuck in Gitmo were stone cold terrorists when we caught them. And we have every reason to believe they’d act as stone cold terrorists again, if anyone was foolish enough to give them an opportunity to do so.

Under the law of war, the U.S. has every right to detain them for the duration of hostilities. And the war on terrorism, a war they started, is still far from over.