American public libraries now handle tasks that look nothing like lending books. The reason is their access model rather than any deliberate expansion of their mission.
The access model is unusual
A library is generally open to anyone during posted hours, requires no appointment, charges nothing to enter, and does not ask why a person came.
Almost no other public building combines those features. Agencies require appointments or eligibility, shelters have intake criteria, and commercial spaces expect a purchase.
Because the door is genuinely open, whatever a community lacks tends to arrive there by default, whether or not the library planned for it.
Digital government made it a service counter
As applications for benefits, permits, taxes and jobs moved online, they came to assume a device, a connection, an email address and a printer.
Households without those things go where they are free, which places library staff in the position of helping complete consequential forms.
Staff must then help without giving legal, medical or financial advice, a line that is difficult to hold when the person in front of them has nowhere else to go.
Physical shelter and its consequences
A climate-controlled building with seating, restrooms and no purchase requirement serves an obvious function during extreme heat, extreme cold and long waits between appointments.
That function brings the library into contact with homelessness, mental health crises and substance use, situations for which librarians are not trained by profession.
Some systems have responded by employing social workers or outreach staff, while others rely on referral relationships, and capacity varies widely between systems.
Funding does not track the added work
Library budgets are typically local and often tied to property tax revenue, so funding reflects local wealth rather than the volume of services requested.
The areas where libraries absorb the most non-library work are frequently those with the least local revenue to fund additional staff.
Because circulation statistics remain a common performance measure, much of the added workload is invisible in the figures used to justify budgets.
The internal debate about scope
Some in the profession argue that this work is a legitimate extension of public information service and that libraries should be resourced for it explicitly.
Others argue that absorbing responsibilities from other agencies allows those agencies to withdraw, and that libraries end up doing social work without funding, training or authority.
Both positions are held sincerely within the field, and how a given system resolves the question depends heavily on local funding, staffing and municipal arrangements.