If Darrell Issa expected John Kerry to abide by a subpoena in the issue of e-mails withheld by the White House on Benghazi, the State Department wants to temper those expectations. Earlier today, spokesperson Jen Psaki offered a suggestion to the House Oversight Committee — find someone “more appropriate” for such testimony:

The State Department is doubling down on its opposition to Secretary of State John Kerry testifying on the deadly Benghazi attack, saying in a statement overnight that a congressional committee should find “a more appropriate witness.”

Kerry will be on a previously scheduled official trip to Mexico on May 21, the day the House Oversight and Government Reform Committee subpoenaed him to testify, State spokeswoman Jen Psaki said in the statement.

Psaki said State Department officials had been in touch with the committee to “determine how to resolve their subpoena,” but she stopped short of confirming that Kerry would ever appear at a hearing related to the Sept. 11, 2012, attack, which predated his time in office.

The militant attack on a U.S. consulate and nearby CIA annex killed Ambassador Chris Stevens and three other American personnel. An independent review panel found that the State Department had ignored requests for more guards and security upgrades and had become too reliant on local militias for security. The State Department has since participated in several congressional hearings and released thousands of documents in response to queries about its response that night.

“Given the pressing foreign affairs issues that the secretary is actively engaged on and the committee’s focus on document production issues, we would like to explore whether there are better means of addressing the committee’s interests, including through a more appropriate witness,” Psaki’s statement said.

That’s diplomatic speak for: Enough already. Find somebody else to testify.

Still, the obvious question can’t be avoided. What difference at this point does this make? Once the Select Committee takes over the investigation, Oversight will have to move on to other issues — probably the IRS scandal. That’s why this little snub from Psaki makes little sense, politically speaking, except momentary self-satisfaction by the Obama administration. State could have just played out the string and waited for Trey Gowdy to start his probe, and then moot the entire controversy by providing full disclosure of documents withheld or redacted in earlier investigations.

Until now, State has played it cool. With Leon Panetta and Mike Morell weighing in with support for the select committee, maybe they should have stuck with that strategy.