Jim Young / Reuters

Updated at 10:21 a.m. ET

America’s NATO allies may be on their own after November if Russia attacks them.

Donald Trump, the GOP  presidential nominee, appeared to make U.S. military support for NATO member states conditional on whether those states have met their financial obligations to the bloc, which has served as the cornerstone of global security after World War II. The comments, in an interview with The New York Times, represent a marked departure from the security policy of every presidential nominee from either of the two major parties since NATO’s founding in 1949.

The Times asked Trump: “If Russia came over the border into Estonia or Latvia, Lithuania, places that Americans don’t think about all that often, would you come to their immediate military aid?” The full exchange is worth reading:

TRUMP: I don’t want to tell you what I’d do because I don’t want Putin to know what I’d do. I have a serious chance of becoming president and I’m not like Obama, that every time they send some troops into Iraq or anyplace else, he has a news conference to announce it.

SANGER: They are NATO members, and we are treaty-obligated ——

TRUMP: We have many NATO members that aren’t paying their bills.

SANGER: That’s true, but we are treaty-obligated under NATO, forget the bills part.

TRUMP: You can’t forget the bills. They have an obligation to make payments. Many NATO nations are not making payments, are not making what they’re supposed to make. That’s a big thing. You can’t say forget that.

SANGER: My point here is, Can the members of NATO, including the new members in the Baltics, count on the United States to come to their military aid if they were attacked by Russia? And count on us fulfilling our obligations ——

TRUMP: Have they fulfilled their obligations to us? If they fulfill their obligations to us, the answer is yes.

HABERMAN: And if not?

TRUMP: Well, I’m not saying if not. I’m saying, right now there are many countries that have not fulfilled their obligations to us.

SANGER: You’ve seen several of those countries come under cyberattack, things that are short of war, clearly appear to be coming from Russia.

TRUMP: Well, we’re under cyberattack.

SANGER: We’re under regular cyberattack. Would you use cyberweapons before you used military force?

TRUMP: Cyber is absolutely a thing of the future and the present. Look, we’re under cyberattack, forget about them. And we don’t even know where it’s coming from.

At issue is NATO’s Article 5 on collective defense, which states that an “armed attack against one or more of them [members] in Europe or North America shall be considered an attack against them all...” The article was invoked once: by the U.S. after the attacks of September 11, 2001—which explains why NATO was involved in the U.S.-led war on Afghanistan. A NATO official, speaking on condition of anonymity, pointed out that after the attacks NATO sent AWACS planes to patrol American skies and deployed a third of the troops in Afghanistan for more than a decade; more than 1,000 soldiers from non-U.S. NATO allies and partners were killed there, the official pointed out.

In a statement, NATO Secretary General‎ Jens Stoltenberg said: “Solidarity among Allies is a key value for NATO. This is good for European security and good for US security. We defend one another. We have seen this in Afghanistan, where tens of thousands of European, Canadian, and partner nation troops have stood shoulder-to-shoulder with US soldiers.”

If Trump is elected in November and is true to his pledge, then few of NATO’s 28 members will qualify for U.S. support in the event of a war. Only the U.S., Greece, the U.K., Estonia, and Poland meet NATO’s guideline that defense spending constitute 2 percent of GDP.

Toomas Hendrik Ilves, the Estonian president, tweeted Thursday morning about his Baltic nation’s commitment to NATO. He did not mention Trump.

Estonia, along with its Baltic (and NATO) partners, Lithuania, and Latvia, were until the early 1990s part of the Soviet Union. Bulgaria, the Czech Republic and Slovakia, Hungary, Poland, and Romania, were, likewise, member of the Soviet-allied Warsaw Pact, NATO’s communist counterpart. When the Soviet Union collapsed, these former communist countries looked to the West for new alliances. All are EU and NATO members. Trump’s remarks are causing jitters because the memory of the Soviet Union is still fresh in these states, and they are increasingly wary at Russia’s muscle-flexing under President Vladimir Putin. (Trump on Putin: “He’s been complimentary of me. I think Putin and I will get along very well.”)

The one NATO ally whom Trump appeared to defend in his interview with the Times was Recep Tayyip Erdogan, the Turkish president who survived a coup attempt last week, and, in response, has purged the country’s institutions of those he believes are responsible, and declared a three-month state of emergency.

“The coup never took place—the coup was not successful,” Trump said, “and based on the fact, and I give great credit to him [Erdogan] for being able to turn that around.”

When questioned whether a President Trump would “press him to make sure the rule of law applies?” the GOP nominee replied:

“I think right now when it comes to civil liberties, our country has a lot of problems, and I think it’s very hard for us to get involved in other countries when we don’t know what we are doing and we can’t see straight in our own country. ... We need allies.”

Erdogan, who has been pressed by the EU and the U.S. on respecting the rule of law in the wake of the coup attempt, has yet to respond.

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