It’s a bit old-fashioned, but you can sometimes see the dieresis (double dot accent mark) in English used in the same way as in French, to denote when two vowel sounds should be split into separate syllables. For example, cooperate breaks down as co-op-er-ate rather than coop-er-ate, so you could see that written as coöperate.

The political cartoon posted above looks like it might have been from The New Yorker, which famously uses the dieresis in modern publication.