The news of the U.S. airstrike killing Qassem Suleimani, head of Iran’s Islamic Revolutionary Guard Corps, and other members accompanying him has unleashed a firestorm of analysis and commentary. Some of that commentary is well informed. Others, not so much.

Much of the details are yet to be known, such as how the United States carried out the attack, the level of coordination that took place (if any) with the Iraqi government, and the reaction to the attack by major U.S. allies and partners. But it will help in the coming hours and days to keep our wits about us.

One pundit unequivocally stated that the U.S. is “now in a hot war with Iran.” No, it isn’t. War is a political decision made by sovereigns or governments, famously defined by the military theorist Karl Clausewitz as “an act of violence to compel our opponent to fulfill our will.”

There are no lists of acts or situations which define when a nation automatically goes to war. Many thought that when Iran shot down a U.S. drone on June 20, that meant the U.S. and Iran were now at war.

But it is how countries choose to react to incidents or situations that determines when a nation goes to war. In the drone case, President Trump and America chose not to view the shoot down as an act of war.

Perhaps the most egregious case for entering into war is when one country invades another, such as when Russia invaded Ukraine and seized Crimea in 2014. But even in this case, Ukraine did not declare war on Russia.

The U.S. has said it doesn’t want war with Iran. The question is how Iran will react. Despite the breathless commentary, it likely doesn’t want a general war with the U.S. So, no, we are not at war with Iran.

Still, other commentators have alleged that Friday’s attack violated international law and that the “use of drones or other means for targeted killing is almost never likely to be legal.”

Contrary to common belief, there is no single rule book of international law governing war and conflict. There is instead a doctrine referred to as “Just War” Theory that has its roots going all the way back to the dawn of history.

This body of thought has been amended by such thinkers as Saint Augustine of Hippo and Saint Thomas Aquinas. Within Just War Theory, there are a set of criteria, one dealing with the conditions appropriate to enter into war, called “jus ad bellum,” and the proper behavior when nations are at war, referred to as “jus in bello.”

Within jus ad bellum is contained the criteria that entering into a war or conflict must be for a just cause. Scholars have typically considered self-defense as a condition that fulfills that criteria. To put it plainly, if you see a person raising a weapon to fire at you, you needn’t wait until you are shot to take action. This criteria is referred to as anticipatory self-defense, and most would agree that if a country’s leaders have sufficient reason to believe an attack is imminent, to protect their citizens they should not be required to endure that attack before they take action.

For a good example, think how the U.S. should react if North Korea’s Kim Jong Un put one of his ICBMs on a launch pad, fueled it, and declared that it had a nuclear warhead, and he was shortly planning to fire it at the United States.

Should we wait and see? Of course not.

The Trump administration has stated that “General Suleimani was actively developing plans to attack American diplomats and service members in Iraq and throughout the region.” Putting aside the death and destruction that Soleimani has caused U.S. forces in the past, taken at face value, this statement fulfills the requirement established in Just War Theory for a U.S. preemptive attack.

There is still much to learn about this incident, but it would serve us well to maintain a disciplined and informed view of the situation.