The US had mag stripes in widespread use first. We are looking at 20 or 30 years ago: most of the rest of the world caught up long ago, but they caught up after the problems with mag stripes were known and so the rest of the world built infrastructure to attempt to fix the now known problems.

Note too that the US has a legal limit of $50 if your card is stolen. As such to the consumer there is no incentive to care about security. Other countries don't have that protection and so consumers rightly refused to take a change until things were more secure. All that security comes at a cost, one consumers cannot afford to gamble on, but to a larger business can call cost of doing business and weigh against the cost of upgrading security.

Other countries have the sort of limits. The banks and processors just storing armed vendors into emv using lower ratesas the carrot and legal requir,nets as the stick.

Most US credit cards are chip and sign (debit uses a pin, but did before chip cards as well). Occasionally I'll see a transaction where the pos wants a pin and the user has no idea what pin because they have never used a pin with that account.