The Crimean crisis, if nothing else, has been a useful reminder of the limits reality places on a superpower. The US may enjoy a level of global military dominance unseen since the days of the Roman Empire, but it is a far leap from there to being able to do anything one wants.

This is not a new lesson. A mere three years ago, during the Arab Spring, Washington discovered that its global reach did not allow it to control massive forces of history. Just as there was little or nothing Washington could have done to prevent Hosni Mubarak’s fall, there is little or nothing Washington can realistically do today to stop a Russian annexation of the Crimea. This is worth remembering as one listens to the clamour on the right for US President Barack Obama to “do something”. Few politicians have gone as far as the talk radio hosts who blame everything happening in Ukraine directly on Obama, but that does not mean they have been quiet.

John McCain, predictably, is calling for military aid to Ukraine’s embattled government and late last week published a piece in the New York Times. He was careful to say that ultimate responsibility for what is happening in Crimea, and what may yet happen in eastern Ukraine, lies squarely with Russian President Vladimir Putin, but also took the view that Obama’s “weakness” in foreign affairs had emboldened Russia’s president. This view was also expressed over the weekend by Bob Corker, the Tennessee Republican who stands to take over the Senate Foreign Relations Committee next year if the GOP takes control of the Senate in November’s elections. “Our administration has created an air of permissiveness,” he told Fox News. “We have to show more resolve. It’s not helpful. It shows wishy-washiness.”

Last week, Ted Cruz, a senator from Texas who is a rising star on the right wing of the Republican Party, told a conservative gathering: “When there is a vacuum of leadership in the world, it is not a good thing for America. It is not a good thing for freedom.” That is fair enough. Many Democrats who detest Cruz would happily agree with that statement. Cruz also said that “no rational person is interested in a shooting war between the United States and Russia”. Again: No problem there. Yet Cruz went on to say “there are a host of steps that we can take that do not involve direct military action with Russia.”

Strictly speaking, this is true. What Cruz and McCain either miss or choose to ignore is that every easy step has already been taken. Serious sanctions — sanctions that may actually hurt Russia — require a united front among western nations. Rhetoric aside, there is little evidence of such a front coming together. Germany’s Angela Merkel is too concerned about her country’s oil and gas supplies. Britain’s David Cameron is too concerned about London’s banking and real estate markets.

Like the Arab Spring, the Crimea Crisis presents American and European policy makers with a series of uncomfortable choices. It is not just that they find political ideals placed at odds with economic and political realities. It is the fact that there is very little they can do about it.

Over the last three years I have used this space more than once to ask what, exactly, the Obama administration’s critics think it ought to have done to ‘save’ Mubarak, Mohammad Mursi, Ali Abdullah Saleh or back in 2009, the supporters of Mir Hussain Moussavi. This question has nothing to do with whether America wanted to see any of these men stay or go. My point is that in each of these situations, Washington (please note: Washington, not Obama. The situation would have been identical under president McCain or president Romney) had only limited influence and certainly no ability to change the basic outcome.

The hubris that comes with being a superpower is the belief that global events are yours to command. The reality confronting those who lead superpowers is the limited extent to which American presidents can actually force events to go their way.

In their sixth year in office, most American presidents understand this. That is probably one of the reasons why Obama has spent much of the last week on the phone to Putin rather than going on television to denounce him. His actions are not a sign of weakness, but rather one of maturity: Of an understanding that America’s tools during this still-unfolding crisis are powerful, but limited, and that the best way to deploy what power America has is in concert with allies. The inherent limitations of this approach may frustrate senators from both parties. It should also be said that, in the end, they may not work. The chance that they may have some positive effect, however, is far higher than the alternative.

Gordon Robison, a longtime Middle East journalist and US political analyst, teaches Political Science at the University of Vermont.