The Fed’s expected interest-rate hike on Wednesday could be the start of something more troubling for investors

Investors broadly expect the Federal Reserve to raise its benchmark interest rate on Wednesday. The hike itself is not what is unsettling markets — it is the possibility that this move marks the beginning of a longer tightening cycle. A single increase is typically absorbed without much disruption, but a sustained path of higher rates changes the calculus for nearly every asset class.

Rate expectations matter because they feed directly into borrowing costs, bond yields and equity valuations. When investors sense that policy is turning more restrictive for longer, they tend to reassess how much they are willing to pay for future earnings, particularly in rate-sensitive sectors such as technology and real estate. Bond prices also come under pressure as yields rise.

What to watch is not just the decision itself, but the Fed's accompanying statement and guidance on the pace of future moves. The tone of that communication may matter more than the headline rate change, since it shapes how markets price the months ahead.