What if my wife is in Saudi Arabia and faces beheading for apostasy? Now do we call out the army, devastate the country and rescue the damsel in distress?
What about arresting the ambassador on trumped up charges? Nukes? We have a lot of them.
How about the hostages in Iran. If it were not Carter we would have (and history shows should have) leveled them and installed a puppet government.
These laws are not designed to protect someone from parking tickets though they do. The principle of the law is valuable. But if you want to end diplomatic immunity think, just for a moment, what might happen to UK diplomats and their families if the host nation needs leverage. You see, with only one exception, the US is powerful enough to extract a terrible price from any country fucking with our people. The UK, not quite so much. In other words, we don't need as much protection as others do. Diplomatic immunity protects the less militarily and economically powerful nations from blackmail by more powerful ones.
This is not a small question regardless of how the US decides it will go.
God is a comedian playing to an audience that is afraid to laugh.