If Britain chose to leave the European Union, the ramifications would be significant. The country, with a $3 trillion economy, would have to rethink its trade deals, its pitch to overseas investors and relationships with foreign companies.
The move would potentially be much more drastic than an exit by Greece, a possibility that roiled stocks and bonds in 2011 and 2012.
Yet global markets are just starting to wake up to the possibility that British voters may decide to break away from the regional pact. Even now, markets are relatively sanguine despite polls showing almost an even split among voters.
"The Brexit vote appears to be a virtual coin flip according to the polls," wrote Jim Bianco, founder of Bianco Research, in a note last week. The markets aren't priced for a "leave" vote, he said.
While the British pound is weakening against the euro and European stocks are declining, there hasn't been a broad-based move away from riskier debt the way there has been in the past.
Consider, for example, the gap between bonds of riskier euro-zone countries compared with those of better-capitalized nations. It has been staying relatively constant, even though it soared in 2010 and 2011 amid the height of Greek angst, when anti-austerity protests were heating up in that nation and European finance ministers hashed out bailout plans.
The gap between yields on junk bonds and investment-grade debt in Europe has actually been narrowing, thanks to the European Central Bank's new initiative of buying corporate bonds.
And investors seeking haven investments are plowing into U.K. gilts as much as they are U.S. Treasuries despite Britain's position at the epicenter of turmoil.
Here's why traders may not be responding more to a possible Brexit. First, central banks may be eclipsing the concern. They have been pumping trillions of dollars into the financial system to numb investors' post-crisis anxiousness. That has outweighed fundamentals lately.
Second, many traders just don't think Britain will truly break away despite what the polls say.
And third, investors have become used to being punished for selling risky assets in response to broad-based fear. Just look at Brazil's bonds, or Greek debt and equities, or oil junk bonds in the U.S. Fear hasn't paid off recently.
Brexit is becoming a more real possibility. While markets are starting to wake up to that fact, they still have a long way to go before they're sufficiently spooked.
This column does not necessarily reflect the opinion of Bloomberg LP and its owners.
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