I’m pretty sure his lawyers and cabinet considered all the pros and cons of every approach.
If Trump declared it a war action, doesn’t the war powers act limit him
“The War Powers Resolution requires the President to notify Congress within 48 hours of committing armed forces to military action and forbids armed forces from remaining for more than 60 days, with a further 30-day withdrawal period, without a Congressional authorization for use of military force (AUMF) or a declaration of war by the United States. The resolution was passed by two-thirds of each of the House and Senate, overriding the veto of the bill from President Nixon.’
You missed the part where I said he could take precedent from President Lincoln’s actions during the Civil War.
Lincoln had no hesitation having opposing lawmakers, judges, etc arrested and held imprisoned during the Civil War.