Given augustus anger over his public humiliation then yes, it was. Was there any politics in the background? None that was directly connected I think. It was purely embarrasement at these youngsters behaviour that got them exiled. Augustus was performing a balancing act during his reign - his own personal power vs the dislike of tyrants/kings/dictators. His detractors would pounce on his families wayward behaviour (as the media does now to our own royal family) and given the murderous qualities of roman politics, then it was essential that such scandalous behaviour was seen to be punished. Augustus was keenly aware that he must show an example as much as preach his moral stance. We regard him as a hypocrite for that reason, but lets not forget that his womanising wasn't unusual for male romans and not considered scandalous. At least he was relatively discrete compared to the arrogant antics of his successors.
Sorry, Caldrail - I have to disagree with you here 100%. Even the most cursory glance through the names of the elder Julia's lovers suggests an attempted coup. I do not doubt that Julia's scandalous sexual behaviour offered Augustus the perfect front for her banishment. Far better to bemoan an errant daughter who fornicated in public than to admit before the Senate and People that his own flesh and blood were conspiring against him. This would have undermined the whole constitution he was trying to create and establish on a firm footing. The younger Julia's adherents were also highly political men. All the elder Julia's lovers were either executed or took their own lives. I really cannot accept that such a punishment - or such a reaction from them - would have been necessary had they simply been guilty of adultery. Why were they so publicly 'named and shamed'?
Above all, Augustus needed to create at least the illusion of a united front within his own family. Factional in-fighting was not to be countenanced - let alone admitted to openly. He had learned that through the crucial events of 23BC. And it was a particular thorn in his successor's side, as we know. Agrippina's support not only sprang from her being the widow of Germanicus, but also as the daughter of the late, exiled Julia, who was a popular lady with the People. Let us not forget that Augustus was often screamed at in the street by common folk wanting his daughter brought back to Rome. So much so that he eventually did relent late in his life, allowing her to return providing that she stayed in Rhegium. There is no record of the Senate's officially complaining to Augustus about either of the Julias' behaviour - only that of Postumus. Had the Senate been ready to complain, why then did Augustus remain in ignorance of her 'wild lifestyle' for so long? Nor did Augustus ever bother too much about what was said about him and his family. Suetonius himself quotes the emperor's famous saying of 'Let us be content that they stop at angry words.' Scandal alone would not have made him act in so harsh a manner, I am convinced of it.
In fact, one of the executed nobles was L. Aemilius Paullus, husband of the young Julia, on a charge of conspiracy, since that of adultery was clearly inappropiate.