The Brits were formerly in the habit of calling them Kafir and Wogs ~
This is just more of the trouble euphemisms will get you into.
The real problem with "Asian" as used by Brits is that it is overbroad.
It includes Middle Eastern, Russian, Indian, Southeast Asian, and "Oriental."
So if you are referring to one of those subgroups (e.g. "looked middle eastern") the only reason to use "Asian" is to obfuscate.
Oddly, weren't many of those muslim, arabic speakers who hijacked the 9-11 AFRICAN (from Egypt)? (Though they, like the subjects of the article "looked middle eastern")