Bloomberg | James Stavridis: Trump�s tweet about destroying them for harassment risks turning a tense situation into a war.

President Donald Trump sent a warning shot across the bow of Iran last week, tweeting that any further �harassment� of U.S. warships by Tehran�s navy in the Gulf would result in the destruction of the Iranian units. The tweet was evidently a response to videos of Iranian ships behaving badly, and intended as a warning to stop small surface combatants � some armed with short-range missiles or guns � from buzzing by U.S. ships at close and therefore dangerous range.

The Department of Defense, when queried about what many see as Trump�s new rules of engagement, simply said that commanding officers already have all the tools they need to respond appropriately to Iran. Translation: Thanks, but we�ve got this covered, Mr. President. How should the U.S. and its allies think about this latest twist on Iran�s campaign to threaten stability in the region?

I�ve got a fair amount of experience in the matter. Back in the long, hot summer of 1987, I was a mid-grade naval officer serving as operations officer on the Valley Forge, a brand-new cruiser fitted with the Aegis guided-missile system that was deployed to the Gulf. The so-called tanker war -- a campaign of Iranian attacks on ships carrying crude -- was in full bloom, and our mission was to keep the Strait of Hormuz open. We escorted Kuwaiti tankers that had be �re-flagged� to the U.S. so that we could legally provide escort service.

The threat from the Iranians was reasonably high due to their land-based Styx cruise missiles, small naval combatants with surface-to-surface missiles, some combat aircraft with air-to-surface capability, and diesel submarines. It wasn�t quite a state of war, but enough so that we spent a great deal of time at battle stations, called �general quarters� in the Navy.

As the ops boss, I was responsible for training the wardroom in the rules of engagement -- the highly detailed, classified directives that determine when and under what circumstances it is appropriate to use deadly force. An Aegis cruiser is mightily armed with its land-attack cruise missiles; anti-air guns and missiles; super-fast Gatling guns called Vulcan Phalanxes that shoot depleted uranium bullets against air and surface targets; .50 caliber machine guns; and various electronic warfare capabilities.

The trick for those standing watch was not finding the right weapon to use if attacked, but rather knowing when (and when not) to use all of that firepower. Our captain, a wise mariner and tactician who went on to become an admiral, used to say, �Remember that when you release ordnance, everything changes.� What he meant was that even a seemingly minor tactical event in a theater of operations thousands of miles from Washington could have major geopolitical implications.

The basis of any decision to open fire against an opponent is straightforward. It is based on either observation of a �hostile act� (someone shooting at you) or a clear indication of �hostile intent� (you deciding someone is about to open fire at you). In such cases, returning fire is unlikely to become controversial; but taking the first shot at an opponent because you think the other guy is about to fire can require complex analysis done in a matter of minutes or less.

Indications of hostile intent can include being illuminated by an opponent�s fire-control radar; observing weapons being pointed in your direction; intercepting radio or other telecommunications indicating an attack is imminent; a general pattern of belligerent behavior; observing combat aircraft carrying weapons headed on an attack profile; or hearing torpedo doors opening under water over a sonar listening device.

During that late-80s deployment, we gave the order to conduct an offensive attack only once, when we observed what seemed like clear hostile intent:�an Iranian combat aircraft on what appeared to be an attack profile headed toward the aircraft carrier we were guarding. Our actions were effective in eliminating the threat, and were deemed appropriate after the fact.

But on many, many occasions, we came close to taking offensive action -- again based on various indicators of what might have almost been hostile intent. It was tense and dangerous duty, and we were glad to accomplish our turn and sail home.

A few months after we departed, another Aegis cruiser, the Vincennes, had less luck. The crew acted on perceived hostile intent against what they thought was an Iranian F-14 armed with air-to-surface missiles. They accidentally shot down a commercial airliner, killing 290 civilians flying from Tehran to Dubai. It was one of the most tragic mistakes the U.S. Navy ever made.

I understand Trump�s intent in warning the Iranian government. But we should remember that all those relatively young officers and sailors in this hot spring of 2020 are already on a hair-trigger alert. They have watched Iran attack tankers and oil fields with missiles, seize and hold hostage tankers and crews, and launch ballistic missiles at U.S. bases in Iraq. The U.S. has responded with a variety of means, including killing Iranian General Qassem Soleimani with a drone strike.

U.S. sailors are well trained. They will not -- nor should they -- respond to �harassment� (which can range from bad seamanship to taunts on bridge-to-bridge radio) unless and until it poses a clear, justifiable and credible threat of hostile action. We don�t want any mistakes or miscalculations in an already fraught environment.

Bottom line, Mr. President: Let the Defense Department and the Navy do the job on the front lines.



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