...she and her husband have, for decades, run a company in the highly politicised commercial fishing industry, where holding on to a licence requires considerable nous and networking skills.
Her rise from parent-teacher association to city council gave her a natural political base in her home town of Wasilla. Going on to become mayor was a natural progression. Wasilla's population of 9,000 would be a small town in Britain, and even in most American states.
But Wasilla is the fifth-largest city in Alaska, which meant that Palin was an important player in state politics.
Her husband's status in the Yup'ik Eskimo tribe, of which he is a full, or "enrolled" member, connected her to another influential faction: the large and wealthy (because of their right to oil revenues) native tribes.
All of this gave her a base ....
...a seat on, and subsequently the chairmanship of, the Oil and Gas Conservation Commission... launched her into the politics of Alaska's energy industry.
Palin quickly realised that Alaska had the potential to become a much bigger player in global energy politics, a conviction that grew as the price of oil rose. Alaska had been in hock to oil companies since major production began in the mid-1970s.
As with most poor, distant places that suddenly receive great natural-resource wealth, the first generation of politicians were mesmerised by the magnificence of the crumbs falling from the table. Palin was the first of the next generation to realise that Alaska should have a place at that table.
Her first target was an absurd bureaucratic tangle that for 30 years had kept the state from exporting its gas to the other 48 states. She set an agenda that centred on three mutually supportive objectives: cleaning up state politics, building a new gas pipeline, and increasing the state's share of energy revenues.
This agenda, pursued throughout Palin's commission tenure, culminated in her run for governor in 2006. By this time, she had already begun rooting out corruption and making enemies, but also establishing her bona fides as a reformer.
With this base, she surprised many by steamrollering first the Republican incumbent governor, and second, the Democratic former governor, in the election.
Far from being a reprise of Mr Smith Goes to Washington, Palin was a clear-eyed politician who, from the day she took office, knew exactly what she had to do and whose toes she would step on to do it.
The surprise is not that she has been in office for such a short time but that she has succeeded in each of her objectives. She has exposed corruption; given the state a bigger share in Alaska's energy wealth; and negotiated a deal involving big corporate players, the US and Canadian governments, Canadian provincial governments, and native tribes - the result of which was a £13 billion deal to launch the pipeline and increase the amount of domestic energy available to consumers. This deal makes the charge of having "no international experience" particularly absurd.
In short, far from being a small-town mayor concerned with little more than traffic signs, she has been a major player in state politics for a decade, one who formulated an ambitious agenda and deftly implemented it against great odds.