Using the guard would trigger insurrection clauses and allow Trump to justify greater violence. Multiple states will have to all do it and trigger a civil war. Trump will not relent in his demand for absolute power. The inevitable end to succeeding at that pursuit is insurrection and then civil war which Minnesota can not afford to incite without alignment with enough other states. It isn't cowardice to do this alone, unless absolutely necessary and when other states have had time to repair for their own rebellions.