In debates about affairs far away, "both" seems to be the hardest word. Ukraine has been a case in point, the discussion reduced to a slanging match of binaries, each side hurling false dichotomies at the other – insisting that every aspect of this unfolding crisis can be reduced to an either/or choice, when in fact the truth very often comes down to both.

So one side loudly condemns Russia for its armed incursion into Crimea, thereby violating Ukrainian sovereignty. What hypocrisy, cry their opponents. How dare the west criticise Russia when the US, Britain and its allies invaded Iraq 11 years ago. That's the choice. Either Russia is in the wrong or the west is in the wrong. You can't have it both ways.

Except you can. It's perfectly possible for a westerner to oppose both Russia's action in Crimea and the invasion of Iraq – indeed, to oppose both for the same reason: as unmerited violations of sovereignty. Admittedly, that might be tricky for John Kerry, given his Senate vote in 2002 giving George W Bush the authority to use military force against Saddam Hussein – a record that should have given him pause before denouncing Vladimir Putin for acting "in a 19th-century fashion by invading another country on a completely trumped-up pretext".

But it's silly to throw the Iraq precedent back at Barack Obama. He is president of the United States, in part, because he opposed the 2003 invasion. It was his stance on Iraq that helped him defeat Hillary Clinton for the Democratic nomination. You can condemn Obama if you like over Libya or the continuing US drone warfare, but the specific example of Iraq does not make his position on Crimea hypocritical. It makes it consistent. To ignore that fact, to hold the current administration responsible for the sins of its predecessor – as if Obama and Bush are simply the interchangeable faces of permanent US power – is to ignore the cardinal principle that in democratic societies governments change. Perhaps not in Russia, where Putin has been in charge since Bill Clinton was in the White House – but in the democratic world, that's how it works.

That's far from the only empty choice offered up in the Ukraine debate. One camp slams the crudity of Putin's lies and deceits – his press conference this week recasting him as a Kremlin version of "Comical Ali", hilariously defying the facts as he insisted that the Russian troops everyone could see with their own eyes in Crimea were in fact Ukrainian civilians who had popped to the local fancy dress shop to stock up on Russian military uniforms. His charmingly retro claim that Russian forces had been invited into Ukraine by the latter's ousted president – just as Soviet troops were invited into Hungary in 1956 and invited again into Czechoslovakia in 1968 – had one commentator suggesting Putin had lost his mind.

Standing against them is the opposing camp, which urges you to look instead at the new forces ruling Ukraine. This camp notes the influence of far rightist groups Svoboda (which traded originally under the historically resonant name of the Social-National party of Ukraine) and the Right Sector, now rewarded with seats in Ukraine's government, and of the fascistic paramilitaries patrolling the streets of Kiev wearing swastika armbands and parroting anti-Jewish slogans. They alert you to the torch-lit parade of ultra-nationalists commemorating Stepan Bandera, hailed a hero of Ukrainian independence despite his wartime collaboration with the Nazis.

Yet it should be possible to face the truth of both these situations, to condemn Putin's de facto dictatorship in Moscow and to be appalled by the presence of fascists in a 21st-century European government in Kiev. Yet too often the warring camps close their eyes to one even as they denounce the other. This goes not only for commentators and pundits, slugging it out online and on air; John Kerry and European Union foreign ministers should realise that it would not undermine their stance against Russian interference in Ukraine if they were to condemn the racist thugs who played a role in the Maidan uprising and have won a slice of power. It is possible to hold both positions at once.

Indeed, to do otherwise is to deny that reality is always stubbornly, maddeningly complex. Take the question of antisemitism, which has become a battleground in the war of words over Ukraine – with Putin casting himself as the defender of the besieged Jews of that country. It is quite true that Svoboda's leaders once claimed Ukraine was ruled by a "Moscow-Jewish mafia" – quite something, given that Jews make up an estimated 0.15% of the country's population – or that they lambasted the Ukrainian-born actress Mila Kunis as a "dirty Jewess". True too that synagogues have been on the receiving end of Molotov cocktails and that one communal leader was frightened enough to suggest that Jews get out of Ukraine for their own safety.

Yet it's also true that young Jews were themselves active in the Maidan protests, even forming their own combat group against the now-ousted government. True too that when Jewish leaders asked Kiev's new authorities for protection for key community buildings, they got it instantly. Nor can one ignore the Jewish leaders who believe some of these antisemitic attacks were performed by pro-Russian provocateurs, bent on discrediting Kiev's new masters, just as one cannot dismiss Thursday's letter to Putin from the Ukrainian Jewish leadership, telling the Russian president to back off and accusing him of both exploiting the issue of antisemitism and hypocrisy, given his country's own record.

Nothing, in other words, is as clear as the antagonists and their cheerleaders abroad would like. It is true that Crimea was part of Russia until 1954, and that it is a quirk of history that it is part of Ukraine – and yet also true that to invade it still breaches international law. Just as it is true that the Russians have not fired a shot in anger, while the invasion of Iraq left hundreds of thousands dead – but that doesn't make Putin's action OK.

It used to be said of Tony Blair that he came to prefer foreign affairs to matters domestic because they afforded a moral certainty missing at home. I've written before of the way some outsiders follow the Israeli-Palestinian conflict as if it were a clash of two rival football teams, mine always right, yours always wrong.

But the world is not like that. It is rarely black v white. It usually requires us to hold two apparently contradictory thoughts in our head at once. Life is not either/or. It is both.

Twitter: @Freedland