Dutch isn't an international language because they just weren't as good at colonisation as Britain, or Spain. (And Belgium would like a word with you if you think no-one else speaks Dutch.)

Look at the international languages before English - Latin and Greek - both beasts of languages to learn. Vulgar Latin's simplified offspring (French, Italian, Spanish) are largely the result of second language learners casting off the bits of Latin they couldn't or wouldn't learn.

I don't believe that English borrows more profligately than any other language. Historically it was hugely influenced by Norman French but nowadays I'd suggest more languages borrow from English than English does from other languages. The eternal fight between the Académie française and the people who actually speak French over borrowed words vs "native" ones is a good example of this.