As others have said, there's 3 cards to carry in your wallet:
1.) Discover IT (5% categories for the quarter).
2.) Chase Freedom (5% categories for the quarter, usually different categories from Discover).
3.) Citi Double cash (2% all the time). Fidelity AMEX also is 2%, but AMEX isn't accepted everywhere, however the AMEX customer service is loads better than Citi.
Int'l Travel: You must own the Capital One card since it gives a decent 1.5% and NO FX fees. You can also own any "flavor of the month" airline miles card. These cards have largely eliminated the FX fee (1st annual fee as well) while collecting the huge bonus as well after you meet the spending threshold.
If you don't want to mess around with signing into categories every quarter and forget what's what with each card, just get the Citi Double Cash and call it a day.
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(I have the Priceline Rewards 2% as my default cash card as it's more generous than Citi Double, but it's no longer available with the same terms as I have for new applicants. I also own the US Bank Cash+ since it gives 5% in two categories and 2% in one category YOU choose. The past two quarters, they've eliminated restaurants, my chosen 5% category, so I've socked it away for the moment).