The global economy has faced another extension of uncertainty as the U.S. Federal Reserve again chose to delay its base rate hike. Early this year, expectations of a hike during the first half were dominant in the market.

The most likely timing for a hike was June, according to earlier bets of global investment banks. And the global market was fully bracing for temporary shocks from a U.S. rate hike, alongside hopes for a fast rebound, as the scenario was sufficiently reflected in the market.

The market dislikes uncertainty most of all. After the June 13-14 monthly gathering of the Federal Open Market Committee, Fed Chair Janet Yellen took an ambiguous stance between a rate freeze and a hike later this year.

Though she opened the possibility of a hike in the third quarter, her message was similar to the one she gave at past gatherings.

As a result, economies across the globe have no choice but to take wait-and-see policies until the uncertainty surrounding the U.S. monetary policy is lifted. There are four more FOMC meetings this year -- in July, September, November and December.

Yellen named the so-called Brexit worries as a key reason the Fed put off embarking on a more hawkish policy this month. It is understandable in a way.

But in another way, there are few paths for the U.S. raise its base rate if it has to contemplate a variety of negative factors in other countries. The Fed had cited China’s slowdown as a factor frustrating its will toward the hike.

According to this logic, the Fed is not the U.S. central bank but the world’s central bank. If so, the Fed will have to take possible terror attacks by the jihadist Islamic State or severe earthquakes into consideration in its rate-setting meetings to minimize shocks to the global market.

The most significant factor for Fed rate-setters should be the economic indices in the U.S. A hike on the basis of an apparent recovery in American economy would bring hope to other countries including major trading partners of the world’s largest economy.

For South Korea, the Fed’s unclear stance has triggered high volatility in the won-dollar exchange rate and fluctuation of the KOSPI index over the past year. Lingering concerns over capital flight have curbed the index’s growth.

In an aspect, it seems that the U.S. is not ready to tolerate a stronger dollar versus major currencies from a rate hike.

The world’s superpower has argued that some export-driven countries were engaging in currency manipulations. This may suggest that the country is concerned about the price competitiveness of its own export items on the international stage.

The Fed might have contemplated the possibility that a spike in the value of the greenback could be a bane to the U.S. economy, which has showed an apparent recovery. As China’s manufacturers, including smartphone producers, are rapidly increasing their market shares, the strong dollar could be a heavy burden for U.S. policymakers.

To other economies across the world, negative effects from U.S. rate hikes appear exaggerated.

During the early 2000s when the U.S. was retrieving bills issued to the market via hikes, stocks in Korea and major emerging countries gained sharply.

In the coming news briefings, Yellen needs to make public the situation of the U.S. economy, such as the outlook on trade balance, in detail, rather than prioritizing factors in other countries.