Basically, here's Trump Jr.'s excuse for the Russian meeting:

[dixiegrrrrl]

13. And those other guys are Trump's son-in-law and his campaign manager

and yet Trump later denied even knowing Manafort and any role in the campaign.
Jared has always been described as Trump's right hand man, remember?

So according to Don Jr, he and Jared and Trump's then campaign manager went to Russia to meet with a lawyer but had NO idea what they were meeting about,
and THEN Don says that the offer to give dirty tricks re: Hillary was a smokescreen for the real meeting topic of...adopting children.

THIS...makes no sense.

"In a statement on Sunday, Donald Trump Jr. said he had met with the Russian lawyer at the request of an acquaintance. “After pleasantries were exchanged,” he said, “the woman stated that she had information that individuals connected to Russia were funding the Democratic National Committee and supporting Ms. Clinton. Her statements were vague, ambiguous and made no sense. No details or supporting information was provided or even offered. It quickly became clear that she had no meaningful information.”

He said she then turned the conversation to adoption of Russian children and the Magnitsky Act, an American law that blacklists suspected Russian human rights abusers. The law so enraged President Vladimir V. Putin of Russia that he retaliated by halting American adoptions of Russian children.

“It became clear to me that this was the true agenda all along and that the claims of potentially helpful information were a pretext for the meeting,” Mr. Trump said.

how could Hillary info be a Pretext for a meeting when he said he had no idea what the meeting was gonna be about?
And if you are then IN the meeting, there is no need for a pretext cause the meeting is now happening.