You need to be careful when talking about ethics in general because the nap is just a small sliver of it. You use nap as the end all for morality which gets you in sticky situations.

For example, you could ask, like Jan helfeld likes to ask, " is it a violation of nap to steal water if you are dying from thirst and the only person with water refuses to give it to you."

Well, the libertarian answer is it's clearly a violation of nap and the owner would be justified in killing you protect his glass of water.

A statist would say, see nap is stupid and can't be followed. Well, hold up a minute. Yes, it's a violation of nap, but the morality of it is not quite clear.

I think most people would say the moral thing to do would be to give the person the water, but there should be no legal obligation forcing you to give the water. As far as the person who steals the water, well yes he committed aggression and should accept the consequences but most people would be sympathetic on moral grounds as to why he stole the water. We would all hope the owner of the water, would be lenient but wouldn't claim he should go to jail if he killed the man trying to steal the water.

Also, say a baby is flowing down a knee deep river drowning. Do you have a legal obligation to save the baby? No you don't, but I think clearly the moral thing to do is get your shoes dirty and save the baby.

So, you can't say that as long as you don't violate nap you are a moral person and vice versa you can't say a person is immoral just because they violated nap.

For immigration, the waters are very murky. For peaceful anarchists trying to cross the border, using force to stop them is clearly aggression. However, stopping someone from coming in who plans to immediately go on welfare and vote for more policies to commit aggression would be justified. So, how do we deal with a heterogeneous population? It's not clear. At this point there are good arguments both ways and saying one is patently false is disengenous