Here is Trump's impeachment articles in 2019.
https://www.congress.gov/116/bills/hres755/BILLS-116hres755enr.pdf
He was impeached for abuse of power by attempting to solicit foreign interference in the US election and for obstruction for refusing to turn over documents.
He was not impeached for weapon sales. Part of his scheme to solicit foreign interference was to hold up aid to Ukraine. It seems you think if I give you something then you actually paid for it. So when are you going to pay up for my giving you evidence of your stupidity? Like most propaganda, yours took some elements of the truth and warped them for your purposes to try to make it seem true while it wasn't. Your propaganda found my truth to be obnoxious because I pointed out your propaganda was nothing more than propaganda based on your alternative truth.
I know what casus belli is. It was simply your attempt to change the topic to something I never said and which wasn't in the article you quoted.