By BRIAN FINLAY
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Last month, President Trump opened yet another front in his tense relations with some of America’s closest allies, firing off terse letters admonishing Germany, Belgium, Norway, Canada, and others, warning them that the U.S. is losing patience with their failure to meet their security obligations under the NATO alliance. The president’s blunt message and scathing remarks have been met with a mix of hand-wringing and outrage at home and abroad. Trump’s detractors, however, would do well to separate the message from the messenger and recall that the longstanding debate over NATO burden-sharing—defense lexicon for the division of responsibilities within the alliance—is as old as the alliance itself. Furthermore, the world may well need the engagement of the non-American NATO allies more today than ever with rising global threats—mass migration, the rise of cyber warfare, and a persistent terrorist threat in an unstable Middle East—coupled with an unpredictable and seemingly isolationist partner in Washington.