Dog was scared. Cup? not so much.
Still a lack of respect.
Big difference between an animal in both arms and cup o tea in only one.
Still not a huge deal. Just another in a long line of disrespect for those BENEATH him.
As President, you know that there will be Marines waiting every time you step off an airplane or helicopter, and that they will be saluting. Making a choice to hold a dog, scared or not, is no different than making a choice to hold a coffee. Both will impede you from making a "proper" salute, and if failing to properly salute is a sign of disrespect, then both are guilty.
But if we want to talk about disrespect for the military, I'd say that it's disrespectful to offer a salute of any kind. Afterall, it's a violation of military protocol for a non-military member to give a salute, and even if you've previously served, you are not to salute while in civilian clothing.