When IS it okay for the president of Country A to ask the president of Country B to look into corruption involving a citizens of Country A?

President Trump called President Zelensky to inform him that the US wanted to investigate certain, possibly corrupt, Americans and that he would welcome his help.

He told Zelensky whom his main points of contact would be.

From that the Dems fabricated grounds for impeachment! They said the aid was held up.

Technically, it might have been but it was paid before the due date. Aid to all countries can be held up when the final checks are being made.

Imagine the outcry if aid had been delivered during the checking process and they ultimately failed the checks? So, standard practice is to place a hold on the aid, do the checking, then release it. In this case no-one in Ukraine was even aware that the aid had been held.

Were any threats made? The transcript says not and President Zelensky also says not.

Was the aid delayed in any way? No, it was paid early.

Was an announcement required? Well, none happened and the money was paid anyway so whatever Sondland thought Giuliani was relaying from the President it seems to have been immaterial.

When they have entered into a mutual cooperation , law enforcement  pact .

Much like the pact the US and Ukraine entered into .

According to American democrats it is a high crime, as bad as treason to ask another country to investigate corruption involving one of its citizens..........In fact American democrats believe this so much they actually tried to impeach President Trump for doing just that.

Because the MSM told the moron party from country A that the citizen had already been investigated and cleared and because the people in the moron party are so gullible they believed them but finally some of the morons are starting to wake up because Pedo Joe is starting to fold like a cheap suit

The President didn't ask for that. Instead, he asked for an anoucement of an investigation on television, which would have tied the hands -- the televised announcement would have prevented a proper investigation and prosecution if the citizen had been involved in the corruption.

But he wasn't trying to look into any corruption. He was looking into getting an announcement on television.

Ask any time they want to ask.
It was the black mail of not paying (with holding) of congress approved payments that used to be illegal.  It is now alright to with hold approved payments if you want something and you are president just do it.  That's the way the repubs decided it should be.
Arch - you have a complete misunderstanding of the issue.