For instance, in 1999, two senior Chinese colonels wrote an officially sanctioned book entitled Unrestricted Warfare.

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And Communist China is operationalizing its ability to engage in what its military planners have described as "unrestricted warfare" - a strategy for using every instrument of power, from traditional and unconventional weaponry to financial attacks and terrorism - to decisively defeat the United States.

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In 1917, Germany announced it was instituting a policy of unrestricted submarine warfare.

CNN: Saturday,

Outraged, yes, but it took two years and German resumption of unrestricted submarine warfare in early 1917 (which Mr Roberts strangely postpones to that September) to bring America to war surely the longest reaction-time in the history of galvanism.

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But within six months, Germany's resumption of unrestricted submarine warfare and meddling in Mexico led Wilson to send American troops to fight in Europe -- an enormous departure from the U.S. tradition of avoiding conflicts outside the Western Hemisphere.

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