Thus far in his presidency, Barack Obama has gone 11-0 in presidential vetoes — eleven wins, no overrides. His predecessor George W. Bush went 12-4 while Bill Clinton had a 37-2 record. If Obama’s record holds up, he’d be the first president since Lyndon Johnson to throw a shutout on vetoes, and just the fourth in a century.

Will Obama risk his perfect record to veto a popular measure that allows victims of the 9/11 attacks to take Saudi Arabia to court over the deaths of family members? And will he risk Democratic chances just weeks before a national election? The Hill says yes:

President Obama is poised to take one of the biggest gambles of his final year in office by vetoing a popular proposal empowering the families of 9/11 victims to sue Saudi Arabia.

Democrats put on a brave face Wednesday, insisting that Obama’s effort to sink the bipartisan bill won’t hurt their party in the elections.

But Republicans are ready to pounce, hoping to use Obama’s opposition as a campaign messaging tool portraying the president — and by extension, Democratic presidential nomineeHillary Clinton and down-ballot Democrats — as siding with Middle Eastern oligarchs over the victims of the deadliest terror attack in America.

Obama and his fellow Democrats will defend a veto with an argument that’s actually not bad — theoretically speaking. The rationale behind a veto rests on the principle that nation-to-nation relations should go through diplomatic channels rather than the judiciary. The Constitution gives the executive branch near-plenary powers in foreign policy, with only the Senate as oversight on treaties and appointments. The judiciary plays no constitutional role in foreign policy at all, so opening up diplomacy to lawsuits intrudes on constitutional division of power … or so the White House will argue.

They will also argue that this will touch off an avalanche of reciprocal lawsuits in other countries, and they’re probably right about that — not to mention an avalanche of nuisance lawsuits in this country. I wonder which ally of the US will bear the brunt of that? (Hint, hint.) Don’t forget that the US has conducted drone strikes in various countries over the last decade or so, with its unavoidable collateral damage. That alone will generate tons of lawsuits all over the Middle East, and perhaps beyond, depending on where family members live now.

The theoretical constitutional argument has one practical hole in it, however. The families of 9/11 victims see the federal government as part of the problem when it comes to determining Saudi Arabia’s role in the attacks. Both the Bush and Obama administrations refused to release intelligence dealing with that question, so the people with standing in this potential case have been frustrated by the government’s lack of action. Hence, Congress has finally passed a bill that would give them more freedom to pursue the truth and a measure of justice on their own. The courts can then force evidence and testimony to determine whether there’s an actual case against Saudi Arabia or not.

Vetoing that bill, as The Hill notes, basically puts Obama and Democrats on the side of the Saudi royal family, no matter how they pretty up their arguments. What’s more, it’s becoming clear that Democrats as well as Republicans have no intention of leaving themselves in that position, and an override is a very likely outcome:

Speaker Paul Ryan said on Wednesday he expects the House will vote to override any presidential veto of a bill that would allow the families of 9/11 victims to sue Saudi Arabia, despite his concerns that the measure could touch off a wave of retaliatory lawsuits.

“I really don’t know the answer to that question,” Ryan (R-Wis.) said when asked if the House would take up a veto override this month before Congress prepares to leave until after Election Day. But Ryan did not say exactly when he expected the override vote to happen.

“It depends on how long it takes for us to get our other work done. I heard that the Senate majority leader said they’re going to stay so if we’re in and they pass it, then it’s going to come over here and we’ll pass it,” he added.

McConnell says the Senate will stay in session for an override, even with the pressure of the election and the need for incumbents — most of them Republicans — to go home and campaign. A veto on this bill might be worth weeks of campaigning anyway, and Democrats know it.

How certain is an override? Neither the House or Senate bothered to conduct a roll-call vote two weeks ago in passing the bill; it was popular enough to pass on acclamation in both houses.  If Obama vetoes the bill and wants to get Democrats to come along to block an override, he’ll need at least 34 in the Senate who are willing to go on the record as opposing the “Justice Against Sponsors of Terrorism Act,” an action that will likely spell the end of political careers. If Obama vetoes it, don’t expect a stampede down Pennsylvania Avenue to join Obama for the photo op.