Can anyone translate to normal English ;) or just explain what means:
"Ass-kissing on the Hill is a skill"
Certainly, it can be explained in one word, Politics.
The hill refers to Washington DC. Ass kissing refers to doing whatever is needed to make someone, usually a superior or a powerful official happy.
Doing this while still maintaining some dignity, respect, and scruples is a significant skill.
I hope this answers your question.