Ever since emails released last week showed New Jersey Gov. Chris Christie's deputy chief of staff ordered the closing of access lanes to the George Washington Bridge, Christie's GOP supporters have struggled to respond. Since then, the party apparatus has chosen not so much to defend Christie as to attack President Obama.

Republicans have launched two main lines of attack. First, they argue, Christie's Bridgegate scandal is no worse than Obama's IRS and Benghazi scandals. And second, they insist, at least Christie showed leadership, unlike Obama. But on closer examination, neither one of those arguments hold water.

First, it should be painfully obvious that the main difference between the Bridgegate scandal and the IRS or the Benghazi story is that we have direct evidence in New Jersey that a top official in Christie's own office ordered the action at the heart of the scandal. In contrast, there's no evidence anyone in the White House ordered the IRS to delay 501(c)(4) status for Tea Party groups or that anyone in Obama's inner circle ordered the military not to respond to the attack on the U.S. consulate in Benghazi.

Just today, a newly released Senate intelligence committee report found no evidence supporting right-wing claims that officials deliberately tried to prevent the U.S. military from responding in Benghazi. And the report confirms that Ambassador Susan Rice followed the intelligence community talking points when she appeared on Sunday morning shows on September 16, 2012.

As for the IRS, I'm not convinced there ever was a scandal there in the way Republicans suggested. The IRS scrutinized both liberal and conservative groups for tax-exempt status. And there's no evidence anyone at the White House ordered them to target right-wing groups in particular. But to follow the GOP's twisted logic is to assume President Obama personally knew about the activities of a mid-level IRS staffer in Cincinnati but Gov. Christie should not have known about the actions of a top aide in his own office.

It's really that simple. When someone can show President Obama's deputy chief of staff ordered retribution against his political enemies, then we can talk comparisons. Until then, that argument is bogus.

But for Christie, his problems extend beyond his top aide. As the governor explains it, we're supposed to believe his deputy chief of staff simply woke up one day and decided on her own to cause a massive traffic jam on the world's busiest bridge on the first week of school, on the anniversary of 9/11, and the beginning of Yom Kippur. That strains credibility. Why would she do such a thing unless she was acting on orders from someone else or was acting consistently with the culture of retribution and bullying in Christie's own office?

But Christie handled his scandal better than Obama has, Republicans claim. "At least he accepted responsibility and fired people," cried an editorial in Investors Business Daily. "On the numerous Obama scandals, the president has not," the editorial argued. And Christie gave "a master class in how to handle a national political scandal," an op-ed argued on the right-wing Breitbart.com website. "It was the anti-Obama approach," the author wrote.

But did Christie really take responsibility? "I have 65,000 people working for me every day. And I cannot know what each one of them is doing at every minute," the governor said at his press conference. That hardly sounds like a man who recognizes his own accountability for what took place.

Perhaps Christie's biggest failure of leadership is that he refused to acknowledge how his own bullying behavior could have contributed to the retribution in the first place. "What did I do wrong to have these folks think it was OK to lie to me?" Christie asked at the press conference. But that missed the point. The question Christie should be asking is: "What did I do wrong to encourage my staff to create the traffic jam in the first place?"

It is Christie's failure of self-examination that ultimately may have led him to dismiss the importance of the controversy from the beginning. Although the governor claims he acted "swiftly" as soon as he found out about the emails, that assumes you forget the four months he spent ignoring, denying and mocking the charges when they first came to light last fall.

This again reveals a failure to investigate from a man who was once the U.S. attorney for New Jersey. Surely Christie knew of the massive four-day traffic problem back in September. Why didn't the governor ask David Wildstein, a former official in the Port Authority of New York and New Jersey, about it when the two of them met during the height of the crisis? And why did Christie think Wildstein and Deputy Executive Director Bill Baroni resigned from the Port Authority just last month if there was no controversy until the emails came out last week?

To make matters worse, it seems Christie still hasn't learned his lesson. Asked about the Port Authority's David Samson's role in the scandal, Christie said last week, "I am convinced that he had absolutely no knowledge of this." But the emails explicitly said "Samson helping us to retaliate." If Christie believed the emails were true about his aide Bridget Kelly, why wouldn't he believe they were true about Samson?

Let's face it, Bridgegate is a major scandal for the Christie administration. And it's not going to blow away by facile and clumsy Republican attempts to compare it to Benghazi or the IRS or whatever the GOP's anti-Obama hashtag of the day happens to be.  

Keith Boykin is a New York Times best-selling author and former White House aide to President Clinton. He attended Harvard Law School with President Barack Obama and currently serves as a TV political commentator. He writes commentary for BET.com each week.

The opinions expressed here do not necessarily reflect those of BET Networks.

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