PRESIDENT Obama this week began cracking down big- time on tax havens — and he’s enlisted Rep. Charles Rangel to help. Will this dynamic duo be swift and fair in meting out tax justice? It shouldn’t take long to find out: After all, if Rangel and Obama are looking for culprits, they can begin in their own offices.

Start with Harlem’s favorite Democrat, who heads the tax-writing House Ways and Means Committee. As The Post noted in an editorial yesterday, Rangel has dodged his tax liabilities on his Dominican villa and helped save friends taxes in exchange for a school bearing his name.

But the fattest chapter in the “Annals of Rangel Tax Scams” covers his efforts on behalf of tax dodgers in the US Virgin Islands. The islands aren’t a “tax haven” in the strictest sense — but they offer many benefits of offshore tax jurisdictions.

And as The New York Sun reported in 2003, some wealthy money-managers who lived and worked in Chicago and New York exploited these tax breaks by claiming the USVI as their place of residence — and escaped nearly 90 percent of their income-tax bills.

Congress cracked down with the 2004 American Jobs Creation Act, requiring USVI taxpayers to demonstrate a sustained physical presence to claim residency. The threshold was set at 183 days a year.

Seem reasonable? Not to Rangel. In 2006, USVI officials praised Rangel for his “vigorous” support of efforts to drop the residency requirement to 122 days a year over three years. The move to make it harder for mainlanders to avoid taxes in the USVI, Rangel said at the time, was “not fair.”

So in March 2006, Rangel hijacked the “technical corrections” process to try to push through the 122-day requirement. “Technical corrections” bills fix errors in the language of legislation that prevent it from fulfilling Congress’ intent. Usually the corrections are handled in a nonpolitical way, but according to Ways and Means staff Rangel’s team killed one such bill and stalled another, holding out for watered-down USVI “residency.”

Then, in November 2007, The Washington Post reported that Rangel sponsored a bill to block IRS audits of hundreds of Americans who’d claimed the USVI as their place of residence, perhaps illegally. Rangel’s bill limited to three years the amount of time the IRS could go back to examine suspected USVI tax frauds, a move the Joint Committee on Taxation estimated would deprive the US Treasury of $38 million over 10 years.

A spokesman for Rangel on the committee, Matthew Beck, said yesterday the move was an effort to bring the USVI statute of limitations for audits into line with those on the mainland — and he denied that Rangel “held up” any bills. “Chairman Rangel has not supported tax havens in the Caribbean or anywhere else,” Beck added.

Presumably Rangel’s support also had nothing to do with the $112,500 Virgin Islands donors put into his coffers during the last three election cycles.

The administration also merits some scrutiny — particularly the co-chairman of the President’s Council of Advisers on Science and Technology, Harold Varmus, Obama’s point-man on the stem-cell decision. He is president of Memorial Sloan-Kettering Cancer Center in New York — which, according to its 2007 IRS 990 form, maintains an “office” in Bermuda.

Sloan-Kettering’s chief financial officer says the “office” is just “a drawer in a file cabinet” that legally allows the hospital to avoid paying higher taxes on malpractice insurance. CFO Michael Gutnick says buying the insurance in New York would be prohibitively expensive, because the state’s high taxes get factored into premiums. Not so in Bermuda, where the hospital has had dealings for about six years. (Before Bermuda, it was the Cayman Islands.)

Now the hospital is in the process of moving the insurance to Burlington, Vt., saying it hasn’t been able to find the “talent” in Bermuda to manage the insurance adequately. For six years, though, it was willing to reap the financial benefits of Bermuda’s lower tax rates.

What was that in Obama’s speech about “ending tax breaks for companies that ship jobs overseas”? Sloan-Kettering is a 501(c)3 nonprofit, and Gutnick says the maintenance of overseas captive insurance policies by tax-exempt hospitals is “commonplace.” Will Obama end that mega-tax break for organizations that ship insurance jobs overseas, starting with the hospital run by his own science adviser?

Don’t hold your breath.

Meghan Clyne is a DC writer.