Something that could give a massive boost to the world economy isn't going to happen

In a world of anemic economic growth, it seems that everyone from central banks to small businesses are looking for a catalyst to kick the world's slow growth into high gear.

One of the loudest calls has been for some form of government fiscal stimulus. Hedge fund titans, Wall Street CEOs, economists, and both parties' presidential nominees have all called for more public investment to drive demand.

The problem is, despite calls for more generous fiscal policy and the strong possibility it could boost the economy, it doesn't appear that it's going to happen, according to Andrew Sheets, chief cross-asset strategist at Morgan Stanley.

"There was broad agreement among our team that higher investment by developed market governments, funded by borrowing at record-low yields, would be a positive for growth and markets over the forecast horizon," said Sheets in a note to clients.

"However, major fiscal action was deemed unlikely, due to political gridlock in the US, a lack of flexibility on budget rules by the European Commission, and limits in the size of what the Abe administration can effectively deliver in Japan."

The argument for fiscal stimulus is simple: Central banks have reached their limit in getting more money into the economy through interest rate cuts and asset purchases, but growth is still low.

Meanwhile, fiscal stimulus has a similar goal of increasing demand in the economy: Build bridges or water treatment plants and you give people jobs and they can then go and spend their new income.

The issue, at least in the US, is that such stimulus requires issuing debt and increasing the deficit. That position is, to put it mildly, not very popular among politicians. This could leave the world economy with little firepower left to stimulate growth, added Matthew Hornbach, a interest rate strategist at Morgan Stanley, in the same note.

"With that backdrop, fiscal policy becomes more important," he wrote.

"But the constraints that politics place on the global fiscal policy outlook should allow uncertainty and weak private demand to retard the little progress major developed economies have made."

With central banks seemingly out of ways to drive economic growth and no stomach for stimulus from governments, there is little reason to think that the slow growth the global economy has been stuck with is going to pick up anytime soon.