It seems ALL credit card car rental insurance provided by US-issued cards for rentals outside of the US is PRIMARY. Of course some countries are excluded, so it would be good to have a list of excluded countries for each card. The most troublesome point is that you must be able to decline the CDW and it is often obligatorily included in the rental rate outside of the US, so you there is no way to decline it. And even though CDW may be effectively obligatory, it can have a high exclusion, on the order of USD 2000 or more, and I have never found any credit card at all that will cover that risk. Please post if there is some way around this.