With Russian troops pounding Ukrainian cities for the seventh consecutive day, President Volodymyr Zelenskyy has urged US President Joe Biden and the North Atlantic Treaty Organization (NATO) members to impose a "no-fly zone" over "significant parts" of the country.
Even British Prime Minister Boris Johnson was confronted by a Ukrainian journalist during a news conference about protecting the skies.
"The Ukrainian people are desperately asking for the West to protect our sky. We are asking for a no-fly zone. Ukrainian women and Ukrainian children are in deep fear because of bombs and missiles which are coming from the sky," Daria Kaleniuk asserted, as quoted by the BBC.
The prime minister politely rejected the request, and claimed that whatever European countries can do is already being done.
So, what exactly is a no-fly zone? Why are Russia's enemies so hesitant to impose it?
What is a No-Fly Zone?
A no-fly zone is an area established by the military of a country or an alliance over which certain aircraft are not allowed to fly.
It is, during times of conflict, imposed in order to prevent an adversary from attacking or surveilling the country that is being protected by the no-fly zone.
It is not like a usual flight ban, like what the US has done with Russian flights.
A no-fly zone has to be enforced, that too by military means.
That implies that if, hypothetically, NATO does impose a no-fly zone on Ukrainian skies, it would have to shoot down Russian aircraft that are flying in those restricted skies.
"You don't just say 'that's a no-fly zone'. You have to enforce a no-fly zone," says former US air force general Philip Breedlove, as quoted in Foreign Policy magazine.
And direct engagement with Russia is the last thing that NATO wants at the moment.
Why the West is Hesitant
Taking down Russian jets would be an act of war. It's different if Ukraine does it, it is already at war with Russia.
But if any NATO country shoots down a Russian aircraft, Moscow will be forced to retaliate against that country.
That retaliation will trigger Article 5 of the NATO treaty, which guarantees collective defence for all its members, and that would lead to a full-blown European war.
The same applies to the United States, hence Biden's hesitation in giving Zelenskyy what he wants.
White House Press Secretary Jen Psaki explained this to reporters earlier this week on 28 February: "Well, here’s what important for everybody to know about a no-fly zone: What that would require is implementation by the U.S. military. It would essentially mean the U.S. military would be shooting down planes – Russian planes. That is definitely escalatory. That would potentially put us into a place where we’re in a military conflict with Russia. That is not something the president wants to do."
Circumstances Are Different From the Past
It is not as if no-fly zones have not been enforced before.
The US and its allies successfully deployed them over Iraq and Bosnia in the Persian Gulf War and the Bosnia War, respectively.
They were also imposed over Libya in 2011.
Curtailing Russia in the skies, however, is a whole different ballgame.
In the earlier examples, western forces were vastly superior the aerial forces of the militaries led by Saddam Hussein or Muammar Gaddafi.
That is not the case with Vladimir Putin's military strength.
At this moment, the war between Russia and Ukraine is localised. The moment a NATO member gets militarily involved or affected, dozens of other countries are obligated to join the war.
That is why the West is proceeding with full force when it comes to sanctions, but not when it comes to troops or no-fly zones.
(With inputs from BBC and Foreign Policy.)
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