Recently resurfaced comments in which Joe Biden described the need to build a border fence and punish employers for hiring "illegals" are pure political gold for President Trump's reelection efforts.

When CNN dug up a video of Biden speaking hawkishly about immigration at a 2006 talk before a South Carolina rotary club, much of the focus was on how it could be used against him in the Democratic primary. But the comments could prove an even greater problem in a general election, should Biden be the nominee.

"Folks, I voted for a fence, I voted, unlike most Democrats — and some of you won't like it — I voted for 700 miles of fence," Biden said. "But, let me tell you, we can build a fence 40 stories high — unless you change the dynamic in Mexico and — and you will not like this, and — punish American employers who knowingly violate the law when, in fact, they hire illegals. Unless you do those two things, all the rest is window dressing."

He went on: "Now, I know I'm not supposed to say it that bluntly, but they're the facts, they're the facts. And so everything else we do is in between here. Everything else we do is at the margins. And the reason why I add that parenthetically, why I believe the fence is needed does not have anything to do with immigration as much as drugs. And let me tell you something folks, people are driving across that border with tons, tons, hear me, tons of everything from byproducts for methamphetamine to cocaine to heroin and it's all coming up through corrupt Mexico."

In a general election, one of the major contrasts that Democrats are going to want to draw with Trump is on immigration. But it becomes much more difficult to attack Trump on the issue when there are comments of Biden sounding a lot like Trump talking about all the drugs coming in from Mexico and touting building a fence and saying anything short of punishing employers is "window dressing."

Sure, Biden could argue it was at a different time in a different context, that he was speaking about it as part of a broader immigration reform that was more compassionate toward immigrants.

But it could allow Trump to muddy the waters, as well as make Biden seem opportunistic and insincere on the issue.

A similar thing happened in 2012, when the parallels between Obamacare and the healthcare law Mitt Romney championed as governor of Massachusetts undermined Republicans' ability to attack Obama's unpopular law during his reelection campaign.

Editor's Note: Updates to clarify Biden's point about "window dressing."

