OK. You're entitled to your opinion.
We see that there was a major problem that developed in the 4th. century between the established church of the Roman state and a significant amount of other Christians.
Indeed. At one point the empire was 70% Arian. You make a lot about anti-Arian emperors, but not so much about anti-Niceaen emperors.
What emerges is the fact that orthodoxy emerges despite the desire of emperors to determine the doctrines one way or the other.
I do not for one moment believe that it was all about one man .. Arius.
Nor do I, just answering your original point.
Constantine, with his emperor hat on, wanted to unify the state and church, and presided over an ecumenical council. The "Jesus is God" view was voted in, and he enforced it.
And as the evidence shows, emperors had a hard time enforcing anything.
before his death.
There seems to have been considerable doubt that he considered the vote representing true faith in his mind,
.wouldn't you say?
Oh, no doubt.
Eusebius of Nicomedia was related to Constantine, and owed his progression to his influence at court, and the great power he wielded in the church was derived from that source.
During his time in the imperial court, the Eastern court and the major positions in the Eastern Church were held by Arians or Arian sympathisers. Eusebius served Constantine, Constantius II and tutored Julian the Apostate. There is no doubt he promoted Arianism among the royal family – his infliuence is probably greater than Arius'.
The Arian influence grew so strong during his tenure in the imperial court that it was not until the end of the Constantinian dynasty that it lost its influence in the empire. Eusebius modified Arian belief somewhat, to make it more palatable, and he is considered the leader and organiser of the Arian movement after Arius.
At Nicaea he signed the Confession, but only after a long opposition. His continued defence of Arius angered the emperor, and a few months after the council he was sent into exile due to his continual contacts with Arius and his followers. Three years later, it seems he succeeded in regaining imperial favour by convincing Constantine that Arius and his views do not in fact conflict with the proclaimed Nicene Creed. After his return in 329 he brought the whole machinery of the state government into action in order to impose his views upon the Church.
Eusebius was a skilled politician. Upon his return from exile he regained lost ground and expelled many of his Nicaean opponents, including holders of his office, notably Athanasius, even though Athanasius was regarded as a "man of God" by Constantine. Another major feat was getting himself appointed Patriarch of Constantinople, the expelled Paul I of Constantinople would eventually return as Patriarch after Eusebius' death.
Eusebius brought Ulfilas into the Arian priesthood and sent the latter to convert the heathen Goths.
Even after his death, Constantius II attempted to convert the Roman Empire to Arianism by creating Arian Councils and official Arian Doctrines.
"On the whole, Constantine and his successors made life pretty miserable for Church leaders committed to the Nicene decision and its Trinitarian formula."
Ellingsen, Mark (1999). Reclaiming Our Roots: An Inclusive Introduction to Church History, Vol. I, The Late First Century to the Eve of the Reformation
. Pennsylvania: Trinity Press International.