For the first time in a generation, the world’s major economies sank together last year, the Wall Street Journal is reporting this morning. Now most appear to be perking up in unison as well — further evidence of how the fates of far-flung nations are increasingly interlinked.

For much of the past half century, national economies largely rose and fell according to local factors. Germany, for instance, was hammered in the early 1990s by the fallout from reunification. Japan saw an asset bubble burst, and the U.S. was waylaid by a savings-and-loan crisis.

But links among national economies began tightening in the 1980s, as trade and foreign shareholdings steadily grew. Then in the 1990s a boom in cross-border mergers and corporate investment bound them together even more closely.

The binge of global expansion forged a new channel capable of zapping economic change swiftly around the globe. Thanks to the communications revolution, executives respond to shifting conditions in faraway markets in real time. Big companies have world-wide supply chains, so that profits and losses — and even the mood — in one country can affect hiring and investment decisions in another.

So just as the corporate links last year helped pull the world’s economies into the first lockstep recession since the oil shock of the 1970s, they now seem to be coordinating a synchronized upturn. A host of indicators from around the globe have risen together at a surprising clip.