The Russian invasion of the Ukrainian mainland — which people in Kiev have expected since Moscow’s infiltration and then annexation of Crimea in March — has now begun. While Russia denies it has again marched in to seize a part of Ukrainian territory, fewer and fewer people believe it.

Ukrainian President Petro Poroshenko’s government is officially telling people not to panic. “Ukraine has the means to defend itself,” Poroshenko told the National Security Council. “In these days, we are in a true fight for Ukraine’s independence.”

Oppositional newspapers and some pro-government outlets in Moscow have been reporting that the country’s paratroopers have already been fighting and dying in southeastern Ukraine, citing their families. NATO, meanwhile, says that well over a thousand Russian troops have already crossed into Ukraine. Ukrainian officials say that number is much higher — quoting figures of up to 15,000 men. And as the sun set over Kiev on Thursday night, there were more and more reports of Russian tanks heading for Ukraine.

They are entering a country that is exhausted and in despair after months of revolution and war.

In Kiev, as elsewhere in the country, hundreds marched in support of Ukraine’s sovereignty yesterday afternoon. On the steps of Poroshenko’s office, people stood quietly, draped in flags. Eurovision winner Ruslana Lyzhychko led the crowd in a rendition of the national anthem. But there were few cheers afterwards.

Even Ruslana — now a folk idol in Ukraine due to her support of the country’s pro-European protests over the winter — looked crestfallen and worn out.

“We don’t know what to do,” said journalism student Solomya Dekartch as she watched the speeches outside the presidential administration. “We don’t know how to stop Russia. And [Europe’s] sanctions haven’t made it stop either.”

The atmosphere in Kiev has shifted sharply since the start of what the country calls its “anti-terrorist operation” in the country’s industrial south-east.

“It is unclear if Ukraine could repel a sustained Russian invasion, even with aid from abroad.”

In the early summer, Ukraine’s army and pro-government militias (often recruited on Facebook) seemed to be making gains against pro-Russian separatists. At the time, most of the pro-Russian militias in the Donbass Valley were inexperienced locals under the charge of Russian officers, sources in pro-Kiev battalions say.

Back then, residents of the country’s capital expected an swift victory over the insurgents. But now, pro-government battalions are collecting donations of clothes for the winter ahead. Military strategists expect that this war will continue for at least a year.

And discontent is mounting at the Ukrainian military command’s management of the war.

“Our troops have spent the past week surrounded by the Russians in Ilovaisk,” said Vitaly, a volunteer with the Donbass Battalion who declined to give his last name, referring to a town an hour west of where MH17 went down. “We have asked the government chiefs for help. But until now, we have received nothing.”

There is also frustration in Kiev at perceived hitherto ineffective aid from Ukraine’s allies in Western Europe.

Just a week ago, German leaders, both from the government and the opposition, expressed hope that the economic sanctions they had imposed after the downing of MH17 would be enough to force a Russian exit from Ukraine’s war. But facts from the battlefront have again proved them wrong.

“We need support from America and the West,” said Misha Bogachov, a student also present at the rally outside Poroshenko’s office. “Ukraine cannot win a war against Russia’s army, even if we could win against the [separatists].”

Maybe Ukraine will get that support. Eastern European countries such as Poland appear poised to deliver arms to their neighbour. The United States could join them.

That notwithstanding, it is unclear if Ukraine could repel a sustained Russian invasion, even with aid from abroad.

And nothing so far — not diplomatic negotiations, terse UN sessions, or restrictions on Russian capital — has made Russian President Vladimir Putin back down in his bid to regain Ukraine for the Kremlin.

“Its hard to be at home right now. I am so afraid,” said technician Vlad Holovko amid the crowd outside Poroshenko’s office.