The weird zigzags of a ship trying to navigate the U.S.-China trade war

It's rare that a perfect illustration of a trade war comes along.But a ship full of an obscure crop called sorghum has become a token of what canhappen.

The ship has been zigging and zagging through the ocean for weeks, trying to navigate an ever-changing trade landscape as the U.S. and China exchange tit-for-tat tariffs.

As Beijing and Washington heat up their rhetoric and actions against each other, the circuitouspath of an 80,000-tonne dry bulk carrier demonstratessome of the things that gowrong when countries throw themselves into the path of shipments that make up global trade.

On March 18, bulk carrier RB Eden left the port of Corpus Christi, Texas, loaded with 70,223tonnes of sorghum, bound for Shanghai where the load was destined to become animal feed.

But theswirling winds of a global trade warwere about to throw the vessel wildly off course.

In March,U.S. President Donald Trump announced steep tariffs on steel and aluminum, which hesaid targeted Chinese firms that had flooded the market with cheap, inferior alternatives.

He later stepped up his assault with$60 billion in tariffs on other Chinese goods. It didn't take long for the Chineseto respond with tariffs of theirown, and on April 18 Beijing slapped punitive tariffson a suite of American crops including sorghum.

The Eden was rounding the Cape of South Africa, headed for theIndian Ocean, whennewsbroke that its entire shipment would be subject to a tariff of up to 178per cent.

That's when the ship's owners apparently changed theirminds. Theyheaded the vessel for friendlier waters, reversing direction and plotting a courseforCartagena in southern Spain. As the 230-metre ship meanderedback north, the U.S. and China lobbed new tit-for-tat tariffs at each other. First whisky. Then cars. Then soybeans.

By May, theEden had made it to the Mediterranean. And that's just about whencooler heads began to prevail.

The first sign of a potential thaw came when Beijing announced it would drop itssorghum tariff. The next day, U.S Commerce Secretary StevenMnuchin was meeting with officials in China, and announcedthe trade war was "on hold."

Soon after, Trump visited his favourite port of call Twitter to weigh in on the spat.

He later added that American farmers could soon look forward to a bumper crop of business coming from the Chinese agricultural market he was opening up.

With the trade winds now blowing in the other direction, the crew of the Eden set upon another new course, this time, for Singapore. With luck, its days of U-turns and course changes are over.

There are cliches about how hard it is to turn a ship like that around. It's not easy, and every extra second the ship and its crew spend in the water costs money.

But theEden's meanderingrun to Asia is just one example of how these threats and counter-threats have a real-world impact. Bloomberg reported this week there are as many as 10 other ships loaded with sorghum headed for China.

Shipping analysts say the U-turn would have cost as much as $1.6 million. It also meant the ship wasn't competing for other contracts. That, in theory, at least would have been a positive for the shipping market, because one less ship was out there bidding for cargo, saidBasilKaratzas, CEO ofKaratzas Marine Advisors & Co.

He said it's not common, but at times of high uncertainty you can see ships make multi million dollar U-turns in the middle of the ocean. Just think back to oil prices approaching $150 a barrel a decade ago.

"[Back then]a shipment of oil was sold several times while in transit," he said. "Tankers were making zig-zagging moves in the oceans as every buyer gave different sailing instructions to the captain of the tanker."

The strange tale of the RB Eden makes upjust a tiny fraction of the tensof billions of dollars Americans ship to China every year. Soit's a safe bet the circuitous path of theEden has been replayed in similar ways over countless industries and shipping lanes as American businesses shoulder the brunt of the uncertainty caused by trade wars.

At publication time, the Eden was rounding the western coast of Africa, chugging along at just over 12 knots, a pace that would get it to Singapore at the end of June.

But as with anything else in this unfolding trade war,it's anyone's guess what tempestsmay blow it off course before then.