This is not an academic study and I may have made some errors, but I was curious about the history presidential military service and tried to capture that in this thread:

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Group 1 coincides with the first century of the nation where a number of presidents had been generals with a few mid-grade officers.

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Group 2 in the early 20th century had no military service.

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Then there's Group 3 which starts with Ike but then the rest (for the first time) were USN/USNR and junior- to mid-grade officers and ends with those who avoided service, so a steep downslide in military experience.

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When you add their VPs, it looks like this (note far more who had no military background:

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So for the past twenty-five years or so we have POTUS' and VPOTUS' with either no military experience or numerous deferments.

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But what else has happened during this same period? The rise of retired general and flag officers endorsing candidates, perhaps to mitigate this service gap and validate the worth of the candidate as a CINC.

What will that mean for 2020 or beyond? Will this trend continue?
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