Nice. The dragon starts to squeeze us. Trade wars rarely end well. Especially in the middle of a world-wide depression.

China, which has been blocking shipments of crucial minerals to Japan for the last month, has now quietly halted shipments of those materials to the United States and Europe, three industry officials said on Tuesday.

China mines 95 percent of the world’s rare earth elements, which have broad commercial and military applications, and are vital to the manufacture of products as diverse as cellphones, large wind turbines and guided missiles. Any curtailment of Chinese supplies of rare earths is likely to be greeted with alarm in Western capitals, particularly because Western companies are believed to keep much smaller stockpiles of rare earths than Japanese companies.

China experts said on Tuesday that Beijing’s assertive stance on rare earths might also signal the ascendance of economic nationalists, noting that the Central Committee of the Communist Party convened over the weekend. . .

The signals of a tougher Chinese trade stance come after American trade officials announced on Friday that they would investigate whether China was violating World Trade Organization rules by subsidizing its clean energy exports and limiting clean energy imports. The inquiry includes whether China’s steady reductions in rare earth export quotas since 2005, along with steep export taxes on rare earths, are illegal attempts to force multinational companies to produce more of their high-technology goods in China.

Despite a widely confirmed suspension of rare earth shipments from China to Japan, now nearly a month old, Beijing has continued to deny that any embargo exists.

Industry executives and analysts have interpreted that official denial as a way to wield an undeclared trade weapon without creating a policy trail that could make it easier for other countries to bring a case against China at the World Trade Organization.

So far, China seems to be taking a similar approach in expanding the embargo to the West.