Suppose that Standard Model Higgs mechanism broke electromagnetism, by e.g. veving the charged component of the doublet, so that the photon was massive with $m_\gamma\sim v$. Could such a Universe still have large scale structure? Atoms (i.e. stable electronic orbits)? Life?
Assuming we got past those hurdles, would it have been much more difficult to have discovered special relativity? Would we have been stuck at Galilean invariance, without the invariance of the speed of light from which to build SR? I appreciate that this is speculative.
And, also, the identical question but for a coloured Higgs vacuum that breaks QCD. Would broken QCD still be confining? I guess so - so we could still have nucleons and the resulting chemistry?
In general I wonder how fine-tuned the spontaneous symmetry breaking pattern must be for life/structure. Without EWSB, I know that there are no stable electron orbits, and no life.