Bafan,
Apart from the odd redneck comment, never encountered anything other than positive vibes over the years. I've always felt Americans feel a unique affinity for the Aussies and they certainly don't give us cr@p the same as they do, the Cannucks or Brits.
I think the current administration has emboldened the masses to say what they think, sometimes ignorantly, without thinking first. You get idiots no matter where you work or live but even though I have a very thick skin, I've been surprised at the blatantly personal nature of some of the comments. I should say that it's very much the exception though and working at UAL is easily the best job of my career.