Equity and bond markets have been increasingly volatile in recent weeks as investors have reacted to rising US interest rates, concerns about the escalating trade war between the US and China, and the ongoing Brexit rumblings.
Much of the falls in equity markets in particular are so far down to little more than speculation, with company results remaining broadly robust across many sectors, but jitters are nonetheless turning into something more meaningful as losses start to accumulate.
Are we at the end of the cycle of losses, or the start of something more terrifying such as a sustained downturn?
Time will tell, but there are some potential events which are looming large in investors' minds.
Below Will Hobbs, head of investment strategy at Barclays Smart Investor, looks at three potentially ghastly scenarios which could panic investors.
1. Global debt binge strikes back (again)
This continues to be the favourite choice of prospective economic apocalypse among doom-mongers - the one that perhaps speaks most seductively to our inner puritan.
As measured by global gross debt as a percentage of GDP, the excesses of 2007 represent just a staging post to our current state of bloated excess.
The nightmare: Most asset prices seem crazily reliant on central bank largesse, the band aid which has allowed us to forget that the modern global economy is little more than a debt based confidence trick.
As those same central bankers try to remove their atrophied patients from the monetary drip - as we are seeing in the US right now - this trick could be cruelly exposed, causing equity markets in particular to plunge as part of a long deferred mean-reversion trend.
The reality: But what if the personal perspective on debt was near irrelevant to how we should think about it at the global or even country level?
What if the Great Financial Crisis actually had less to do with aggregate levels of debt and solvency, but rather liquidity - a sudden vacuum of confidence in a system that has always been reliant on it - even before we cast our monetary system adrift from gold?
We also need to remember that debt is also wealth - one person's liability is another's asset. Mortgage debt is an asset for banks; government bonds are held in your pension; debt issued by companies is financed by investors and banks.
We, the consumers, own shares in many of these institutions and even have a claim on government given that it is funded by our taxes.
This points to the fact that at the global level, there can be no net debt, at least not until we manage to find any willing extraterrestrial suckers/creditors. The gross amount of debt owed by the global economy is therefore meaningless in isolation, in spite of the horror it generally provokes.
Furthermore the ‘choke' point for US interest rates for either the US economy or indeed the wider world in aggregate still looks to be some distance from current levels on our estimation.