In some states, if your policy includes coverage for damage caused
by uninsured / underinsured
motorists, and the person responsible was either unknown or underinsured, your insurance company may
end up paying for repairs.
There's no law requiring
uninsured / underinsured
motorist coverage, but you certainly don't want to find yourself at the bad
end of an accident caused
by such a driver who has no means to pay for the damages.