Julian II (the Apostate) and his policies

[TITVS SABATINVS AQVILIVS]

A disaster like Adrianople almost happened 15 years earlier due to Julian's shoddy generalship. He got his army stuck in a tight spot. His incompetence managed to sever his troops from their supply lines and he compounded the fiasco by failing to capture Ctesiphon. Only 60 years earlier Galerius had managed to capture and sack it. And before him Septimius Severus, Marcus Aurelius and Trajan did the same.

Not so easy Theo... Even if Iulianus was maybe too over-cautious, (but just the winners are always right and it's easy to be wise after the event) his generalship and strategy were not so "shoddy".
Iulianus planned well for his campaign, he provided for a reserve force of thirty thousand plus the Arsaces' force of undetermined size. Moreover, burning the fleet he could count on other twenty thousand men too. About sixty thousand men he needed to besiege Ctesiphon in an effective way. Iulianus besieged many cities in Europe and Persia so he was quite experienced about sieges is indisputable. Just his experience was mainly about quick sieges of small/medium sized cities, so his "Prudentia" (that was a uirtus for any roman general) suggested to him to delay the siege till the linking up to the other half of his army that Iulianus knew nearer. And it should be really nearer if Sebastianus and Procopius would have obeyed Iulianus' orders, but they did not, as we know.
But we can also remember that, just before the persian campaign, Procopius received from Iulianus' hands the imperial purple mantle to be guarded with care... Why Procopius (a Iulianus' cousin), if also Procopius was a general in that campaign and so put at similar risks to lose the imperial mantle if captured or killed?

From Matthews, pp. 138-139.

". . . a substantial army under Procopius and Sebastianus was
deployed in the north, to secure the Tigris fiontier against
attack and later, if possible, to link up with Arsaces of
Armenian and ravage parts of Media before jouiing the main
anny in Assyria. . . The failure of the army of Procopius to
achieve the more limited of its objectives was crucial to
Julian's failure at Ctesiphon: . . .".

The Iulianus' campaign was similar to the Traianus' one: splitting the army for a tongs advance from north and west to link up about one hundred thousand men and one thousand and one hundred ships beyond the Tigris to besiege in a serious way Ctesiphon and finally take Persia.

Any general needs of "Prudentia et Fortuna": Iulianus had the first one, not the second one.

Vale,