LONDON, January 8 (WNM/Reuters/Sujata Rao/Dhara Ranasinghe) – Iran's missile attack on U.S. army bases in Iraq overnight sent gold blasting above $1,600 an ounce, boosted the Japanese yen by almost 1% and oil by $3 a barrel.

But it took just hours for that safe-haven dash to fade and for world equities to resume their climb.

It was the second volte face in under a week following a similar pattern of events after the U.S. killing of top Iranian commander Qassem Soleimani on Friday. And that mirrored a super-fast roundtrip on markets after Iran-backed rebels attacked Saudi oil facilities in September.

Welcome to the brave new world where it appears that little short of full-fledged world war between nuclear-armed powers would be required to have a durable impact on financial markets. And even then, some begin to wonder.

By the European close on Wednesday, Brent crude oil prices had returned back below levels seen before Soleimani's death on Friday and Wall Street's S&P500 equity index rallied to new record highs.

At its most basic level, investors appear to believe that Tehran and Washington will avert a broader conflagration. Regionally-contained military blowups and bursts of conflict have proven in recent years not to have a durable impact on either oil supplies and prices nor global economic activity.

Even September's attacks on Saudi oil installations had no lasting effect on crude prices. And beyond the Gulf, years of North Korean nuclear tests and missile launches have not yet escalated nor affected international investment patterns for any significant length of time.

So traders and investors are betting as much on repeated patterns of behaviour rather than on amateur geopolitical reasoning.

"The market has taken a view based on a decade's worth of experience that this is not going to escalate out of control," said Societe Generale strategist Kit Juckes.

"It's the same with the economy. We've had an economic cycle with mini-cycles since 2008 but no recession, we've had trade wars that haven't really turned into real trade wars but keep getting postponed."

And investors who stuck with equities and looked past euro debt crises, North Korean missile tests, Arab Spring revolts, trade wars, Middle East turmoil and unconventional economic policies, have reaped rich returns - world stocks have added more than $25 trillion in value since 2010.

A geopolitical risk index compiled by U.S. Federal Reserve Board researchers Dario Caldara and Matteo Iacoviello rates the Saudi attacks at a relatively high 185 points, but well below the 2003 U.S. invasion of Iraq that scored 545 points.