Laudator Temporis Acti

Tacitus, Histories 1.83.3 (speech of Otho; tr. Kenneth Wellesley, rev. Rhiannon Ash):

You and I are going to war. Surely you don't think that the need for carefully weighing up the situation and arriving at a quick decision when the hour strikes allows scope for every intelligence report to be read in public and every plan to be studied before the whole army? Sometimes it is just as crucial for the ordinary soldiers to remain in the dark as to know things. The nature of a general's authority and the strict observance of discipline requires that even centurions and tribunes should often obey orders without question. If every single man is to have the right to ask why orders are being given, then the habit of obedience is sapped, and with it the whole principle of command.

imus ad bellum. num omnis nuntios palam audiri, omnia consilia cunctis praesentibus tractari ratio rerum aut occasionum velocitas patitur? tam nescire quaedam milites quam scire oportet: ita se ducum auctoritas, sic rigor disciplinae habet, ut multa etiam centuriones tribunosque tantum iuberi expediat. si cur iubeantur quaerere singulis liceat, pereunte obsequio etiam imperium intercidit.

Id. 1.84.2:

Successful fighting, fellow-soldiers, depends on obedience, not on questioning the generals' orders, and the bravest army in the hour of danger is the one that is best behaved before that hour strikes. Arms and courage should be your business: leave to me the job of planning policy and guiding your bravery.

parendo potius, commilitones, quam imperia ducum sciscitando res militares continentur, et fortissimus in ipso discrimine exercitus est qui ante discrimen quietissimus. vobis arma et animus sit: mihi consilium et virtutis vestrae regimen relinquite.