Answered Dec 25, 2018
New Zealand is dependent on other countries in two directions.
Automobiles, trucks, and construction and farming vehicles are imported. Along with petroleum to run them. There isn’t sufficient domestic oil production, although there is a large offshore natural gas field.
Wellington’s newest fleet of commuter trains was built in South Korea. The old fleet was built in Hungary. The new double-decker buses were built in China. Auckland’s newest commuter trains were built in Spain.
Electronic items, ranging from mobile phones to hospital equipment are imported.
Pharmaceuticals are imported. And any of them is “essential” to the people whose quality/quantity of life depends on them.
Sure, we could produce all of the food we need, plus more.
That is the other direction of dependence. This country is very heavily oriented to exporting food, particularly dairy and beef. We need the income from this, and therefore, are dependent on other countries as customers.
One of our greatest vulnerability points is the risk of a food production problem.
There was a serious incident a few years ago, involving allegations of botulinum toxin contaminated milk powder being sold to China. That cost a pile of money, and damaged the country’s reputation, even though it apparently turned out to be a false alarm.
If anyone ever finds even a single case of Bovine spongiform encephalopathy (mad cow disease), whole countries may refuse to accept any more beef exports, for an extended time period. The economic impact of even an accusation would be very serious.
There is a problem right now with Mycoplasma bovis (not found here previously), and a mass-culling of dairy cows. The national impact is about reduced production of milk powder for export.
If other countries don’t want to buy our food, we can’t buy their oil, cars, equipment, phones and other consumer goods, etc.
New Zealand is also heavily dependent on other countries to send us tourists bringing cash into the country.
New Zealand educational institutions (of highly variable level and quality) are also heavily dependent on other countries sending us students (who are effectively viewed as tourists).