Careful: English is just as Germanic as German is. It's easy to conflate "German" with Proto-Germanic and create the incorrect assumption that English evolved from German, when both languages share a common ancestor as part of the West Germanic family of languages.
English has certainly diverged quite a lot, but there are other ways it stayed the same and German diverged; for example, the infamous "th" sounds were at one time common to all Germanic speakers, but was lost among mainland Germanic speakers while English (as well as Icelandic) kept it.
No, because unlike Germany, England was for hundreds of years ruled by a nobility that was French speaking (until English emerged from a blend of French and Old English (which was Germanic).
You could certainly make the case that English is not a Germanic language. You would be in contradiction with the linguistic mainstream, who recognize a direct lineage between Old English, Middle English and Modern English. You would also be placing much import on the influence of loanwords on a language, enough so that the presence of such would divorce the victim language from its linguistic family entirely!
