Travel insurance plans are specific to the country you are planning to visit. So for instance, the coverage and the price for a Travel Insurance policy covering your visit to USA would be different to the policy covering your visit to Australia or Turkey.
The difference in coverage and price is dependent on the currency rate, medical expenses, flight expenses etc at the destination.
Travel Insurance companies also contrive comprehensive plans based on the risks involved at the destination country. Since the risk at a war torn country would be more compared to a country famous as a tourist destination. Hence there would be different Insurance plans for Hawai and Afghanistan.
Another factor to consider is that in some countries travel insurance is mandatory. If you are travelling to any of the Schengen countries or Australia it is compulsory to buy a Travel Insurance policy.
Ensure you read through the policy wordings of your Travel Insurance plan
to be 100% certain of the coverage and avoid any last minute surprises.