A chain of falling stock prices across the world has rocked international financial markets. At the Tokyo Stock Exchange (TSE), where the Nikkei Average fell over 1,000 yen last week, share prices kept declining as the market reopened following the weekend, plummeting over 900 yen at one point on Aug. 24. Behind the downward trend is the fact that the United States is ending its unprecedented ultra-easy-money policy that had been the driving force behind rises in share prices on a global scale.

In other words, the latest chain of stock price declines shows that sharp rises in stock prices, which rely on credit easing without fundamentally improving the economic structure and corporate profitability, never last long. The government of Prime Minister Shinzo Abe should take the latest trends as an alarm bell over its "Abenomics" economic policy mix that relies on the Bank of Japan's ultra-easy-money policy.

At the Shanghai Stock Exchange, the SSE Composite Index plunged more than 8 percent on Aug. 24, offsetting a rise that had continued since the beginning of this year. The Nikkei Average hit a six-month low. Crude oil prices are also steeply dropping.

It is difficult to ascertain how serious the state of the Chinese economy is. Therefore, speculative funds that move swiftly flowed out of Chinese financial markets, triggering sharp plunges in share prices and the Chinese yuan. Share prices had been inflated because of excess liquidity and speculation involving individual investors. No wonder such a situation has been rectified. In a way, however, measures taken jointly by the government and the private sector to raise share prices and the hard-to-reckon monetary policy are amplifying investors' concerns.

Anxiety among investors in China and other emerging economies is closely linked to moves in the United States to end its zero-interest policy.

If extreme monetary policy measures, such as zero-interest and quantitative easing, are prolonged, it can trigger a bubble in share and real estate prices. Excessive money is invested in high-yield financial instruments or land with disregard for their risks, overheating various financial markets across the world.

Critics have warned of such side-effects whenever large-scale credit relaxation was carried out, but each time priority was placed on short-term measures to prop up economies. However, once such an easy-money policy is implemented, governments and central banks tend to rely heavily on the policy and find it difficult to end it. As such, credit easing is just like a poisonous drug.

As soon as the policy is changed to return interest rates to normal levels, speculative investors overreact to risks and quickly withdraw money from markets in emerging economies as well as other markets. As the U.S. Federal Reserve Board is about to end its zero-interest policy and raise interest rates for the first time since June 2006, potential strains caused by its ultra-easy-money policy to the market are beginning to become visible.

The problem is that if normalization of the monetary policy is to be postponed for fear of its impact on share prices and emerging economies, it would not be a fundamental solution. Superficial measures to prop up share prices and use of taxpayers' money to implement economic stimulus measures could not be effective over a long period, and help to cause further strains.

Instead of resorting to such superficial measures, the government should carry out structural reforms and encourage companies to reform their management to increase their profitability.