The Kremlin sends troops across the border, and the United States and its allies cry foul.
It’s happened before — Afghanistan in 1979, Georgia in 2008 — and now Russian President Vladimir Putin has essentially seized military control of the Crimean Peninsula from Ukraine.
The move reflects the still simmering political and social upheaval from the breakup of the Soviet Union more than two decades ago.
What hasn’t changed much are the limited options available to President Barack Obama and European powers to respond to the Kremlin aggression.
The United States and some other countries boycotted the Moscow Olympics in 1980, and Washington helped arm Afghan rebels against Soviet forces, who eventually went back home.
In Georgia, Russia backed secessionist bids in South Ossetia and Abkhazia regions in sovereignty disputes that remain unresolved. The United States and European Union consider the regions part of Georgia.
Here is a look at possible responses to Putin’s latest move in Ukraine:
Unless a sudden escalation causes open warfare between Ukraine and Russia, forget about any kind of U.S. or allied military response.
Secretary of State John Kerry said Sunday the United States was keeping its options open, but he made a point of adding that escalated military involvement would “not serve the world well.”
“The last thing anybody wants is a military option in this kind of situation,” Kerry said on NBC’s “Meet the Press.”
Even veteran Sen. John McCain of Arizona, a proponent of exerting U.S. influence abroad, conceded that the fight must involve diplomacy, not the military.
“There is not a military option that could be exercised now,” McCain said Monday in remarks at the American Israel Public Affairs Committee’s annual conference. “But the most powerful and biggest and strongest nation in the world should have plenty of options.”
John Herbst, a former U.S. ambassador to Ukraine in the administration of Republican President George W. Bush, said one possible military response would be for NATO to agree to deploy additional forces in countries with significant Russian populations.
Herbst noted on CNN that Russia used the need to protect Russian citizens and interests as a pretext for what he called “blatant aggression” in Ukraine now and previously in Georgia.
The annual summit of the world’s industrial powers is scheduled for Russian Olympic venue Sochi in June, but the United States and other members have halted planning for the gathering amid calls for Russia to be kicked out.
Once known as the G7, the group that also includes Germany, Britain, France, Italy, Japan and Canada agreed to add Russia in 1998 to reflect the changing geopolitical dynamic after the Cold War and breakup of the Soviet Union.
Revoking Russia’s membership would isolate Putin diplomatically to deny him the Western acceptance he has sought.
“He will be isolated more. He won’t look good in front of his people,” CNN Chief International Correspondent Christiane Amanpour said Monday.
Such isolation would bolster economic isolation and sanctions — a more effective strategy to pressure Putin.
“The G8 plus some others and all of them, every single one of them are prepared to go to the hilt in order to isolate Russia with respect to this invasion,” Kerry said Sunday on the CBS program “Face the Nation.”
Kerry said foreign leaders were prepared to put sanctions in place to “isolate Russia economically” if Putin does not roll back his forces in Crimea, an autonomous region of eastern Ukraine.
Possibilities include visa bans, asset freezes and isolation by the international community on trade and investment, Kerry said.
Republican Rep. Ed Royce of California, the chairman of the House Foreign Affairs Committee, told CNN on Monday that “the Achilles heel for Russia is their economy — the ruble.”
“We have to lead and we have to rally Europe around a series of steps that would actually impact the Russians economically: sanctions against state-owned banks,” Royce said.
Obama had a lengthy phone call with Putin over the weekend in which the U.S. leader said his Russian counterpart violated international law by sending military forces into Crimea, according to a White House statement.
“President Obama wants to emphasize to the Russians that there are a right set of choices that can still be made to address any concerns they have about Crimea, about their citizens, but you don’t choose to invade a country in order to do that,” Kerry said on CBS.
Putin has yet to make any substantive public statement about the situation, which follows the successful staging of the Winter Olympics in Sochi to bring Putin and Russia some pride in the international community.
The thrust of the Russian position is that it had the right to protect the interests of Russians in eastern Ukraine.
On Monday, Vice President Joe Biden called Russian Prime Minister Dmitry Medvedev to urge Russia to “pull back its forces, support the immediate deployment of international monitors to Ukraine, and begin a meaningful political dialogue with the Ukrainian government,” the White House said.
Separately, National Security Council spokeswoman Caitlin Hayden said the United States has scrapped plans to send a presidential delegation to the upcoming Winter Paralympic Games in Sochi. U.S. athletes still plan to compete.
So far, U.S. legislators have split along party lines, as usual, with Republicans urging a more forceful response while Democrats say the focus should be on Putin, not Obama.
“I think Putin is playing chess and we’re playing marbles,” House Intelligence Committee Chairman Mike Rogers said on “Fox News Sunday.”
“They’ve really been running circles around us. And I think it’s really the naive position on the National Security Council and the President’s advisers that if we just keep giving things to Russia, they’ll wake up and say, ‘Well, the United States isn’t all that bad.’ That is completely missing the motivations of why Russia does what it does,” the Michigan Republican added.
Sen. Lindsey Graham, a Republican from South Carolina, told CNN’s “State of the Union” that Obama needed to offer more than just threats as Putin ramps up military involvement in Crimea.
In particular, he called for reviving plans for a NATO missile defense shield in Poland that Russia opposed.
Democrats quickly rose to Obama’s defense.
“We’re 48 hours into an international crisis,” Rep. Chris Van Hollen of Maryland noted on Fox. “I would hope Americans are focused on condemning the actions of Putin rather than in a knee-jerk way again criticizing the President of the United States. Let’s stand together on this.”