> since without government, there's nobody to stop somebody from starting one.
IMO, this is not the actual problem with the practicality of anarchism.
The problem with anarchism is that the absence of government will recreate the problems which motivate the creation of government, just as excessive government creates the motivation for abolition of government.
Particularly, retaliatory (including lethal) violence—not merely proximate individual and mutual self-defense, but individual and mutual action aimed at preventing future threats from past malefactors, is the common anarchist solution to the problem of perceived-as-unjustified use of force (what, in the context of government, would be “crime”).
But we have plenty of experience with that approach ib areas with no accepted government, weak government, or disinterested government, and what tends to happen is that differences of opinion over whether the initial violence was unjustified (or even if it factually occurred) or the retaliation disproportional (and thus itself unjustified violence) devolve into cyclical violence, the relief for which is establishment of a mechanism for settling disputes about justification and thus either legitimizing or delegitimizing and authorizing corrective responses to force, creating the monopoly on legitimate use of force which, whether called a government or not, defines the state.