Sludge's allegory whilst entertaining is somewhat of an over simplification of international relations, particularly between large powers. As such the truth behind its message is more than a little blurred.
Countries, in particular large powers routinely conduct surveillance of each other. This is a natural fact of international life, like it or not. What Chuck was doing was normal in international terms, and to extend the parable, John would have had one of his mates with surveillance gear stationed outside Dubya's place as well. Leaving aside the morality of such surveillance, the situation offers more interesting analysis.
This interstate surveillance takes different forms. What the EP-3 and Chuck were doing is passive, using long range sensors to probe the electro magnetic spectrum for tell tale signals of somebody else's activity and capabilities. This is much like Chuck sniffing the air around John's house to see what he was cooking. This is all done perfectly legally in intentional air or sea space within the bounds of international convention.
Another more active form is detailed espionage where one country conducts operations on another's soil to learn detailed secrets through devious and illegal means. This is like Chuck breaking into John's house to look what was in his recipe book, and to steal his best recipes. I'm sure none of the powers can claim to be innocent of such activity, especially China which very recently was caught stealing nuclear secrets from US nuclear labs in an effort to jump start their nuclear weapon development program. John/China has not apologised for this incident - which leaves one to wonder why Dubya should apologise for his.
As to Chuck killing John's dog. This is refers to an exceptionally blurred event the Chinese fighter, US plane collision. A US pilot of a lumbering propeller driven plane loaded with sensitive equipment many thousands of miles from home intentionally ramming one of two Chinese jet fighter's close to Chinese airspace seems a ludicrous proposition. In reverse so is, a Chinese pilot in a small jet fighter intentionally ramming the larger US plane. Truth be told we will probably never have a definitive answer except to say that even in passive surveillance things occasionally get out of hand.
A related issue in this tale is what should happen to the plane and crew.
In holding the crew away from US authorities (presumably against their will as they are unlikely to want to defect to China) China will be breaking several international conventions. Given this circumstance should Dubya apologise to John, whilst John is holding Chuck who (we assume) wants to leave?
The plane itself is a different story. International law is ambiguous, though one recent example stands out. During the Cold War a Soviet Mig-25; a then super fast super secret interceptor and pilot defected to Japan. The Soviets understandably asked for their plane back. The US complied, months later after detailed testing of the aircraft, its engines and avionics. The plane eventually returned home to the USSR in containerised pieces. Dubya clearly has little right to ask for a speedy return of Chuck's equipment.
Now ask yourself are such incidents really simple enough to be reduced to a simple story?