Thanks to [Rand al'Thor][1], here's a run-down of modes of transport that we know of that could and couldn't work as international modes of transport:

>Portkeys - yes.
>-
>The answers to [this question](http://scifi.stackexchange.com/q/104395/31394) show that **Portkey travel can be international**. Copying quotes from my and DVK's answers over there:
>
>- from **various places** to **the Sahara desert**:
>
> > "While there have been no proven referee slayings since [1357], there have been several incidences of broom-tampering over the centuries, the most dangerous being the transformation of the referee's broom into a Portkey, so that he or she is whisked away from the match halfway through and turns up months later in the Sahara Desert."
>
> > <sub>-- Kennilworthy Whisp, *Quidditch Through the Ages*</sub>
>
>- from **France** to **the Burrow**:
>
> > Mr. Weasley had therefore gone to meet the Delacours on top of a nearby hill, where they were to arrive by Portkey
>
> > <sub>-- *HP and the Deathly Hallows*, Chapter 6: *The Ghoul In Pyjamas*</sub>
>
>- from **Godric's Hollow** to **eastern Europe**:
>
> > “It was poor little Ariana dying, I think, that did it,” says Bathilda. “It came as an awful shock. Gellert was there in the house when it happened, and he came back to my house all of a dither, told me he wanted to go home the next day. Terribly distressed, you know. So I arranged a Portkey and that was the last I saw of him
>
> > <sub>*HP and the Deathly Hallows*, Chapter 19, *The Life and Lies of Albus Dumbledore*</sub>
>
>Apparition - usually no.
>-
>The answers to [this question](http://scifi.stackexchange.com/q/10236/31394) show that there is some confusion and contradiction over whether or not Apparition can be international. Firstly, as stated in KeithS's answer, this quote from the books tells us that **there is a limit on the distance even a skilled wizard can Apparate**:
>
> > Harry knew it; his scar was bursting with the pain of it, and he could feel Voldemort flying through the sky from far away, over a dark and stormy sea, and soon he would be close enough to Apparate to them, and Harry could see no way out.
>
>> <sub>-- *HP and the Deathly Hallows*, Chapter 23: *Malfoy Manor*</sub>
>
>The following quote from Kevin's answer tells us that it is **possible but risky to Apparate across continents**:
>
>> Apparition becomes increasingly unreliable over very long distances, and only highly skilled wizards are wise to attempt it across continents.
>
>> <sub> -- *Quidditch Through the Ages*, Chapter 9</sub>
>
>And finally, Richard's answer tells us that **Apparition between countries is banned**.
>
>Floo - unclear.
>-
>All the information we have in canon concerns the Floo Network within Britain. This includes the [latest](https://www.pottermore.com/writing-by-jk-rowling/the-floo-network) [articles](https://www.pottermore.com/writing-by-jk-rowling/floo-powder) from Pottermore by JK Rowling. Quoting from the second of these sources:
>
>> Floo powder was invented by Ignatia Wildsmith in the thirteenth century. Its manufacture is strictly controlled. The only licensed producer in Britain is Floo-Pow, a company whose Headquarters is in Diagon Alley, and who never answer their front door.
>
>The inclusion of the words "in Britain" would seem to suggest that there *are* Floo Networks in other countries too, but doesn't tell us whether they're connected.

#Why did Newt use a normal, muggl—*NoMaj*'s mode of transport

We know from the movie *Fantastic Beasts and Where to Find Them* that Newt didn't want to be detected by the **MACUSA**, and we know that most magical modes of transport (including apparition and floo transport) can be traced, detected or otherwise tampered with. From this we can infer that Newt used a conventional NoMaj form of transport to decrease the likelihood of alerting the authorities.

An out-of-universe explanation might be that it is a dramatically boring way to introduce us, the audience, to Newt's arrival to America, compared to the gorgeous, *The Godfather II*-esque imagery of the immigrant ship. It also serves, dramatically, to tell us, the audience, that he is a foreigner in the US, much like we are alien to a magical 1920's America set in the Potterverse, and the movie can achieve this introduction without a single word of exposition to explain it.

<sup><sub>Note: A lot of this is speculation until confirmation starts inevitably pouring in from recent interviews with JK Rowling (and the rest of production team).</sub></sup>

  [1]: http://scifi.stackexchange.com/a/116656/73512