In the past few weeks, just about every positive swing on the markets has stemmed from Donald Trump flagging a possible end to his war with Iran.
But every time the US president suggested there were peace talks going on with Iran's leaders, Tehran has contradicted him.
As market analysts are now beginning to note, it takes two to TACO.
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On tariffs, government shutdowns and threats against Greenland, Canada or Panama, Trump has a history of backing down in the face of strong opposition or an economic slump.
It is why Wall Street has coined the phrase Trump Always Chickens Out (TACO).
But it's not so simple dealing with Iran.
Early today the president said the US had been in communications with Iran's parliamentary speaker Mohammad Baghar Ghalibaf.
"The United States of America is in serious discussions with A NEW, AND MORE REASONABLE, REGIME to end our military operations in Iran," Trump wrote on Truth Social.
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But Ghalibaf swiftly knocked back the claims.
"The enemy promotes its desires as news while threatening our nation at same time. Big Mistake," he said.
"God willing, the people of Iran, under the leadership of the Supreme Leader, will make the enemy regret the aggression and reclaim their rights."
Ghalibaf suggested investors assume the opposite of what Trump has said is the truth.
"Basically, it's a reverse indicator," he said.
"Do the opposite: If they pump it, short it. If they dump it, go long."
Wall Street didn't take Ghalibaf's advice overnight. After Trump's comments, the Dow Jones jumped.
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In anticipation of a major TACO move from the president, Deutsche Bank has constructed a "stress index" to predict when investors should get in.
"If the index rises, the probability of a strategic adjustment by the government increases," Deutsche Bank's Maximilian Uleer said.
"If all four 'pain points' deteriorate simultaneously, the motivation for an adjustment becomes very strong."
But even if Trump wants out of the war with Iran, it won't immediately mean peace in the region.
This morning an oil tanker was struck off the coast of the United Arab Emirates, presumably by the Iranian military.
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Meanwhile, an Iranian parliamentary panel has approved a move to establish an effective toll booth in the Strait of Hormuz.
If codified in Iranian law, all tankers passing through the strait will need to pay a substantial fee.
About 20 per cent of the world's oil passes through the narrow body of water in the Persian Gulf.
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