Cheri Jacobus

Opinion contributor

After months of speculation, educated guesses and connecting the dots, the FBI investigation into just what Russia did to attempt to impact the 2016 U.S. presidential election and who in the United States had dealings with Russians is coming into sharper focus. In fact, there is one thread that may end up as the defining unraveling of the Trump presidency.

Rubber — meet road.

The unverified Steele dossier alleges that Donald Trump offered a quid pro quo to Russia, promising to change the GOP platform language on Ukraine to favor Russia, if Wikileaks would provide his campaign with any salacious and damaging information uncovered from the hacked emails from Hillary Clinton’s campaign and the Democratic National Committee.

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Is that why Trump advisers insisted — even to the point of bullying, by some accounts — that the GOP platform language be changed to make sure it didn't call for giving Ukraine weapons to fight Russian forces? And why do they now tell different stories than they told just a few months ago?

Republicans in Congress have approved providing arms to the Ukrainian government in light of increased Russian aggression, so the strong-arming of platform committee members seemed odd at the time. But the reasons now seem less mystifying.

Trump’s former campaign manager, Paul Manafort, who reportedly has known Trump for 30 years, is now charged with conspiracy and money laundering while working for pro-Russian interests in Ukraine. Trump is claiming ignorance about all of Manafort’s dealings, and complete ignorance about the strange GOP platform meeting where the Ukraine language was changed. Incredibly, Manafort claims he wasn't involved either.

The Trump presidency may very well hinge on the whats and whys of that meeting. The altered stories by various Trump players are the red flags.

Several people who were in the platform committee meeting say Trump campaign aides were present and pushed hard for the pro-Russian change, memorable because it seemed to be the only item they were concerned with. They were on a mission.

Trump campaign official J.D. Gordon participated in the effort and said he was acting to keep the platform language in line with Donald Trump's views. A delegate in the room said Trump campaign staff were on their cell phones talking to the New York Trump campaign headquarters.

Longtime Republican National Convention (RNC) member Diana Denman of Texas was surprised by the aggressiveness of the effort by the Trump staff in the room, and as she wrangled with them over the precise language, the two men said they had to “make some calls and clear it.” She said she didn’t expect to be in a “firefight.”

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Noteworthy, is that J.D. Gordon and Carter Page, another Trump aide, also met with Russian Ambassador Sergey Kislyak at the Republican National Convention.

So just why has Gordon changed his story claiming he did not advocate modifying the language and that he did not act on behalf of Trump? Why did Trump deny he knew anything about the platform change? Who were Trump staff talking with on their cell phones? And why is this so very, very critical?

In what is increasingly looking like a desperate attempt to cover up yet another item of disturbing coziness by Trump Team with Russia, the sudden denials and reversals, rather than exculpatory, actually serve as a bright light with glowing arrows saying “This! This right here!”

It’s a safe bet those RNC platform committee delegates have, or will soon, be having detailed discussions with Special Counsel Robert Mueller’s team regarding that meeting at the convention and what was said and done by Trump staff.

We are being asked to believe that Trump aides were acting independently, that RNC platform committee members are lying, that the ONLY platform change the Trump campaign aides intervened on was done 100% without Trump’s knowledge, and that the dossier is just a complete fake, even though parts have already been verified.

That’s a lot to swallow, even for the most diehard Trump supporters.

Cheri Jacobus, a member of USA TODAY's Board of Contributors, is a Republican consultant and commentator and president of Capitol Strategies PR. Follow her on Twitter: @CheriJacobus.