The piece of text based proof which best backings the surmising that the message Zimmermann sent was vital is The unfamiliar secretary needed to be sure that this message came to von Bernstorff certainly infers a need to get a move on.
He made plans for it to be conveyed on board a U-boat does as well I'd offer something's significant assuming it requires its own boat.
This alludes to the utilization of derivations to arrive at a determination about a thing in light of the accessible proof.
Considering this and from the given portrayal, there is the utilization of surmising to show that the message Zimmermann sent was vital and this was displayed in the reality there was a feeling of crisis.
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