At the moment of writing, it seems sensible to say that, by the time these words appear, Britain and Argentina may no longer be at war. But in fact one cannot say that. For Britain and Argentina have not been "at war." There has been no declaration of war by either nation. There is fighting; there is shooting; there is killing; there is destruction. But there is no war.

By now we are used to this curiosity. Satow's "Guide to Diplomatic Practice" says: "Since 1945 the formal declaration of war between states has become a rare event, and such conflicts as have occurred between states are normally described as 'armed conflicts.' " If he relied only on words which nations now use, a historian would have to say that our age has abolished war.

When he was organizing the U.S. military in an "armed conflict," Robert McNamara said in 1966 that there had been no fewer than 164 internationally significant "outbreaks of violence" in the previous eight years, but that "not a single one of the 164 conflicts has been a formally declared war." Formally, there was no Vietnam War.

Does the absence of formal declarations of war make any difference? The instinctive answer which any thoughtful person will give is that any obscuring of the truth by the refusal to call a spade a spade matters a great deal. War is war. Something very serious is lost when nations can order their own people to kill the people of other nations without saying that they are going to war.

Satow notes that a crucial article of the Vienna Convention on Diplomatic Relations, concluded between 133 nations in 1961, does not refer even to "armed conflict," though "other Articles of the Convention clearly deal with the contingency of armed conflict."

One goes to the dictionary to find three definitions of "contingency": 1. "An event that may occur but is not likely or intended." 2. "The condition of being dependent upon chance." 3. "Something incidental to something else." So the grimness of war is reduced to something not intended, dependent upon chance and incidental to something else.

What is terrifying, when one considers this language of "nonwar," is that it is precisely how all the fearful, grubby, mean wars of our time in fact take place. Those who begin them can appear not to have begun them. They are merely "outbreaks of violence."

To talk of wars as in this manner is to talk of them as we talk of an "outbreak of measles." We do in fact commonly say that "War broke out between Britain and Germany on Aug. 4, 1914" -- but that is not what happened. Britain declared war on Germany on Aug. 4, 1914. Britain went to war, by command of its government.

Britain also went to war with Germany on Sept. 3, 1939, and it went to war with Argentina, not when it dispatched its fleet, perhaps, but certainly when it sent it into action. That I happen to think the British cause is just is irrelevant here. What I am saying is that, rightly or wrongly, Britain went to war, and should have declared war.

Who declares war on whom is important. By his gratuitous declaration of war on the United States on Dec. 11, 1941, Hitler saved Roosevelt from what would have been the awkward necessity to do it himself. When he broadcast to the Germans that morning, boasting that he had brought America into the war, many of them who remembered 1917 despaired. It matters as a fact of history that he made the declaration.

When Britain declared war on Germany in 1914, Germany had attacked not it but Belgium. When Britain declared war on Germany in 1939, Germany had attacked not it but Poland. This is the paradox: It was not the aggressors in either world war who declared war.

The aggressor does not declare war, partly to gain the advantage of surprise -- but partly also because he hopes to avoid war; because he hopes, both literally and metaphorically, to "get away with murder."

Hitler would have liked to take Poland in 1939 without going to war with Britain, and of course he had more or less convinced himself that this would happen. Similarly he more or less convinced himself that, if he attacked Russia in 1941, Britain would not declare itself to be Russia's ally, and might even become Germany's ally against Russia. The aggressor always hopes to avoid general war.

It has been predictable since April 2 that, at the first serious act of war -- the sinking of the Argentine cruiser -- any romantic enjoyment of the war would evaporate, that a quiver of horror would run through everyone. A friend who is not inclined to demonstrate or march for peace nonetheless glanced at the headline Monday morning and said, "That's an awful lot of lives."

By Tuesday evening, more lives lost, this time British. The voice of my friend had changed: ". . . this senseless war," it spat out. "I don't know about that," I responded, "but I never thought it would be pleasant."

The friend I am quoting was only one of many American friends who were enjoying the British response. Enjoying. The word was in fact used to me by another American last Sunday morning -- an artist, no less -- "Aren't you proud to be British? . . . It's so great to have a war that one can enjoy." I bet she has stopped enjoying it.

I had barely absorbed the headlines reporting the loss of HMS Sheffield when the voice of the first friend said out of the blue: "I'm sorry." I wondered what she was apologizing for. "Sorry about what?" I asked. "You've lost one of your boats." It was a profoundly moving remark.

Even the word "boats" was telling in its commonness. But it was the "your" on which the sentence hung. My boat? HMS Sheffield mine? And the answer, of course, the only answer, is, "Yes, my boat." For it needs to be emphasized that this was the American whose stomach first lurched at the loss of Argentine lives. Yet the "your boat" tells of no less human a feeling.

It would be very convenient to overlook, as many people seem able to do, the calls which Loyalty and Patriotism and Nationality, and even something so abstract and perverse as nationalism, make on us all. It would be very convenient to think that we feel equally about a loss of "their boat" or "your boat." But it is not how we are. As a third American friend said to me, when I mentioned the remark about "one of your boats," her mother has told her: "When I listened to the names of the ships they sank at Pearl Harbor, I felt that they were my ships."

This is where our day-to-day speech connects with the conventional language of diplomacy, and so the formal declaration of war. What the declaration of war says -- in language defined by convention and treaty over the centuries -- is that war is a serious business. The aggressors do not think it is serious -- take Belgium, take Poland, take the Falklands -- but our boats go painfully to war.

There is a huge difference between Hitler's declaration of war on the United States in 1941 and Roosevelt's and Congress' declaration of war on Japan three days earlier. Hitler acted alone. After Hitler had spoken, Gen. Jodl phoned Gen. Warlimont. Warlimont protested: "We can hardly undertake this job like that." Jodl answered: "Well, see what you can do." That is exactly how a junta goes to war: See what you can get away with.

In the absence of a declaration of war by Britain, I see no reason why Britain should expect to find an ally, as the United States found it very difficult to find an ally in Vietnam. If you go to war, which aggressors always try to avoid, the rules are clear, the lines are clear and the choices are clear. By not delaring war, Britain has made itself look like a pirate. As a British newspaper said: "BRITANNIA WAVES THE RULES."

It seemed to waive the rules, when it sank that cruiser, because it had not declared war; it could not find the language in which to declare war as Britain did in 1914, as the United States did ically, in 1917, as Britain did in 1939, as the United States did in 1941. It left itself a pirate; and that is why "my boat" stricken seems so senseless.

If there is no war, why kill people? The refusal to declare war is a submission to the lawless: to the aggressor, to the guerrilla, to the terrorist, to the incendiary, to the revolutionary. Our democracies must recover the formal language of war; otherwise no one will ever know who is the aggressor or pirate.

Conventional, formal language always has this effect: appearing to be pedantic, nit-picking, it is the most reliable language of all. It forces us to consider why "you've lost one of your boats." For the very best of reasons: We went to war. Deliberately. With intention.