That's interdependence as it was understood before 1930. Thus the New Zealand economy crashed in 1879 after a crash of a Scottish bank that had speculative investments in land in many colonies, and the Australian depression of the 1890s was triggered by the collapse of Barings Bank in 1890 on account of the financial failure of the Buenos Aires water supply company. There are forces at work, however, that do synchronise economic activity. Crudely put, the other forces relate to fashions of economic policy and economic psychology. It is problems of political economy that precipitate global crises.
Fashion is applicable to diagnosis as well as to treatment.
Thus the identification of inflation as public enemy number one is as fashionable as is the high interest rate remedy. An example might be every country trying at the same time to squeeze inflation by raising interest rates. The result is higher domestic costs worldwide, higher savings, less investment, and no impact on exchange rates. High interest rates worldwide can only mean a world slowdown. Similarly, policies to boost exports while cutting imports, applied everywhere at the same time, generate a world depression.