Chip & PIN is not the answer to online fraud
Worrying about the US using chip and signature is silly. That's only for credit cards, debit cards are chip and PIN. The reason chip and signature is so prevalent is because use of credit cards is so prevalent in the US. Not because we are mindless consumers (well not only for that reason) but because the fraud laws are VERY consumer favorable for credit card fraud, not so much for debit card fraud! That, combined with the better rewards for credit cards make it STUPID to use debit cards for payment in the US. Honestly, anyone who does is a moron, unless they are one of those people with poor impulse control who has learned the hard way they should not have access to credit.
The answer to online fraud is virtual card numbers. They experimented with them a few years ago but the infrastructure on the consumer side wasn't ready. Now, thanks to smartphones using Apple Pay and Android Pay, it is. I should be able to start up Apple Pay on my phone, hit a "generate payment" button, enter the payment amount, and be given a one time code good only for that amount for the next five minutes. I enter that into an online site where it asks for the credit card number, the now-unnecessary expiration and CVV fields are greyed out when it recognizes it as a one time use code, and I'm done. The banks should be happy to pay Apple 0.15% on each such transaction (and even more happy to pay Google 0%) since it would almost completely eliminate that 0.4% of online fraud.
If you took too long it would put up an error "one time use code expired, please generate a new one" and you could hit the button to re-generate another in the same amount as the last one. If the site has their DB hacked and they get your one time use number, who cares, it is only good for one purchase, of that exact amount, and only for five minutes after being generated! If the site has problems connecting to the bank to authenticate your one time code you could always pay via the old method - and the site would be punished by the credit card company charging a higher fee on that transaction, so it would behoove them to make things easy for online shoppers to pay with a one time code.