Upvote:3
...military standards with pagan imagery on them...
That kind of imagery is violating the Jewish / Christian first commandment, something that their god did not look kindly upon (you might remember that episode with the golden calf).
...would the Jews and Christians also view them as rival Gods?
I do not think it has much to do with "rivalry". For a devout Jew / Christian, there is only one god, everything else is a falsehood anyway. So it doesn't matter (IMHO) "how much" the emperors were considered to be gods (by the Romans); according to Jewish / Christian tradition, considering them divine at all is in direct violation to their scripture, and tolerating such worshipping -- which displaying idols on military standards is, in a way -- would amount to complicity.
In other words, even if they didn't dance around a golden calf themselves, they also didn't want to be found near anyone who did. Collateral damage and such.
So the question of "godhood" does not come up in the first place; it is the worshipping as if they were gods that got Jewish / Christian hackles raised.
Upvote:6
The deceased emperors were not proclaimed gods (deus), they were proclaimed god-like (divus) or the most god-like (divinus). The temples erected after their deaths or during their lifes were dedicated to the emperor's genius (something like guardian angel). It was believed that all people had such geniuses that protected them.
If somebody refused to venerate the emperor's genius, he would be seen as somebody who does not want good luck to the emperor or even maybe wants his death.