The stock market’s volatility gauge is near an 18-month low. Why aren’t debt-ceiling, recession and banking fears taking a bigger toll?

What, me worry?

A U.S. debt-ceiling showdown, recession fears and renewed banking jitters didn’t get stock-market investors worked up this week. Major indexes ended April on a positive note, while the Cboe Volatility Index VIX, a closely watched measure of expected stock-market volatility sometimes referred to as Wall Street’s “fear gauge,” closed Friday at a nearly 18-month low.

Called…