Gas prices are down but that isn't fuelling Americans' optimism

Many factors are conspiring to make the US public fearful despite the low oil price but investors should recall that markets tend to climb a 'wall of worry'

The latest season of House of Cards got a lot of things right except (small spoiler alert) the price of gas. Francis Underwood, our sociopathic slimeball in chief, is facing an economic crisis thanks to sky-high gas prices. In the real world gas prices haven't been this low for close to a decade. In January there was a station in Ohio pumping gas at $1.20 a gallon. And yet, just as in Underwood's world, fear spurred by economic uncertainty roils the land.

Gasoline prices are now more than 20% below where they were a year ago, leaving a lot more cash in the pockets of most Americans. In times gone by, lower gas prices seemed all that was required for a mini-flurry of optimism to take hold, in both the economy and the stock market. But not this year - not by a long shot.

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