Barack Obama is basically agreeing with the GOP in praising the Supreme Court’s decision today striking down D.C.’s ban on guns in the home — a very careful position that should appeal in red and purple states, but nevertheless is providing ammo for the Republicans’ flip-flop assault.

And it could also be a real problem for liberals.

First, the GOP wasted no time in blasting out e-mails detailing purported Obama flip-flops on guns, including questionnaires unearthed by the Clinton campaign that said Obama supported gun bans. (Team Obama says he did not fill them out, though his handwriting appears on one page of one of the documents.)

In a statement, Obama praised the Supreme in language that gun-rights types should only find mildly annoying. “I have always believed that the Second Amendment protects the right of individuals to bear arms, but I also identify with the need for crime-ravaged communities to save their children from the violence that plagues our streets through common-sense, effective safety measures,” Obama said.

“The Supreme Court has now endorsed that view, and while it ruled that the D.C. gun ban went too far, Justice Scalia himself acknowledged that this right is not absolute and subject to reasonable regulations enacted by local communities to keep their streets safe. Today’s ruling, the first clear statement on this issue in 127 years, will provide much-needed guidance to local jurisdictions across the country.”

But, compare how California Sen. Dianne Feinstein viewed that “guidance,” especially the part that tossed out triggger locks.

“I happen to believe that this is now going to open the door to litigation against every gun safety law that states have passed – assault weapons bans, trigger locks, and all the rest of it,” Feinstein said today.

“Unbelievably, this decision also strikes down the DC trigger lock requirement, which simply ensures that the gun won’t be used by someone who steals it, or finds it, or doesn’t own it. I think this is a monumental decision.”

Incidentally, Wayne LaPierre agrees with Feinstein that it is now open season on gun laws everywhere. “I consider this the opening salvo in a step-by-step process of providing relief for law-abiding Americans everywhere that have been deprived of this freedom,” the NRA boss told the AP.

The topic is a tough needle for Obama to thread, and we suspect some of the left may actually take a new look at Ralph Nader.