Finally got these done after starting them in July. (I like 50 sentences; can't you tell?) Most of them are about the Vietnam War or related events. A few reference specific events of the war.
Also, I'm not terribly familiar with Vietnam's character, but I tried to do as much digging as I could. I hope she shows up in the new season of the anime! (I do think it's official now - good thing, too, since it's been exactly a year since the last episode aired.)
Air
Vietnam choked at the sight of the mangled corpses of children and women—one holding a baby—lying in pools of black dried blood in the small hamlet that now knew violence instead of peace.
Apples
Like Adam, America had failed to protect his Eve from sin and death.
Beginning
It started innocently enough—how could it have changed into something this terrible, this divisive, this frightening?
Bugs
The way his people always protested but hated protests, always fought but always spoke of peace, always promised but broke promises—it felt like a painful insect bite that itched but hurt to scratch.
Coffee
After America introduced her to coffee, she always drank it with lots of milk to mask the bitter flavor.
Dark
For her, trusting him in this war was like being told to walk step by step into a dark, isolated room and being promised he would—eventually—let her out so she could see a happier world.
Despair
As he walked along the street, America saw another one of his people hold his draft card in his hand and clench his fist, cursing the war that snatched away his future and forced him to live a life of despair.
Doors
When one closed, another opened, they said, but she was still waiting for hers to open while all the others slammed in her face.
Drink
France held his glass against America's and, with a chuckle, said, "To the one we both lost."
Duty
All heroes had a duty to protect others, but even heroes failed.
Earth
She held her head in her hands, unable to bear the damage his chemicals had wrought on her beautiful landscape.
End
In the end, he had been able to do nothing for her—the fruits of his labor were deaths, humiliations, and broken hearts.
Fall
This war had been his Fall—he had gone from an innocent nation who could never lose a war to a man who knew despair and depression.
Fire
Just as she could never escape the smell of napalm, so too could she never free herself from the flames it ignited all over her land.
Flexible
He always noticed the way she walked: smoothly, gracefully, elegantly, her body long and supple and flexible.
Flying
He rode in the helicopter with them; he was an accomplice to their crimes, but as the bombs fell, he made himself close his eyes and look away.
Food
He found it shocking that she was the only person who didn't mind if he ate with his mouth open; everyone scolded him for his rude manners, but she said nothing.
Foot
He carried her so she wouldn't step on any shrapnel left from the war…
Grave
…He carried her, even as he walked to what was meant to be her grave.
Green
What was once delight was destroyed; what was once love was lost; what was once green was gone.
Head
Sometimes, America wished his presidents used their heads—didn't they know their actions would lead to this?
Hollow
Her heart was empty with France, it was empty with Japan, and now it was empty with him.
Honor
His people had none—how could they run around the village slaughtering everyone without so much as a second thought?
Hope
For so long, she had dismissed any faint flickers of hope in her heart, but now, as he held her, she wondered if she had been wrong to despair.
Light
He watched on the television screen as Saigon lit up with fire, then clutched his chest in pain as the Viet Cong fought into his embassy—he thought the city was supposed to be shining with festival lights, not burning with the flames of war.
Lost
He remembered the time one of his soldiers had lost his way in the jungle… but he couldn't stand to think of what happened next.
Metal
She tasted blood in her mouth from biting her lip too hard—the taste was cold, metallic, and bitter, just like the war they were both tired of fighting.
New
The first time he returned to her land, she calmly held him close, knowing everything was safe and all right between them again.
Old
The war had ended years ago, but just as his people would never forget those terrible nineteen years, so too would the world never forget how far America had fallen from the height of his power.
Peace
It eventually came, but not the way he wanted—he hated to abandon her and let her people suffer, united but divided, at peace but at war.
Poison
It slowly circulated in her blood through her body, soaking into her tissues, but there was no antidote for the poison he spread all over her land.
Pretty
She didn't care for her appearance, trying to conceal herself by crossing her arms and moving about awkwardly, but he couldn't understand why she didn't just look at herself and realize her beauty.
Rain
Although it fell in torrents, it could never extinguish all the fires.
Regret
His people hated how so many had died; his president hated how he had lost honor; he hated how he had broken her heart.
Roses
He gave her a bouquet of the beautiful flowers—but she rejected them: They were symbols of love.
Secret
It was no secret how completely broken she was, no matter how hard she tried to hide it.
Snakes
The little slithering creatures curled around her heart, squeezing it tighter until she thought it would burst.
Snow
They watched together as it fell, chilling the world as they struggled to stay warm.
Solid
His will was changing—melting from a hard lattice to a loose conglomeration of dying desires.
Spring
She watched the small buds open slowly, peering at the warm sunshine, and wondered if she too could one day open her eyes to happiness.
Stable
The situation was constantly changing, always moving from one extreme to the other—how long before their hearts completely shattered from the strain?
Strange
She was a stranger in her own land to her own people; could she be their country any longer?
Summer
It was a hot summer—the situation was becoming more worrisome, more men were losing their lives, and the war was heating up from freezing to burning.
Taboo
She wished he would stop making an idiot of himself—didn't he understand her people and customs were different from his?
Ugly
The country was hideous—bomb-scarred, blood-stained, ravaged, ruined, destroyed—but the woman was still strangely beautiful.
War
He didn't know how it had escalated; she didn't know why it had begun.
Water
She dipped her toes into the sea as they sat together, staring at their reflections, looking at the people they had become.
Welcome
He was surprised when she greeted him with a small smile, of all things, and held out her hand—welcoming him back to her country after long years of pain and separation.
Winter
Everything had cooled down now, with the Cold War reverting to its previous chill, but the fires of hatred and misunderstanding still burnt in hearts of their people, disillusioned and disheartened.
Wood
They walked through the trees, looking at the little light peering between the leaves, and hoped for the day when that little light would be a full sunbeam brightening their lives.
Regarding "Food": It's a Vietnamese cultural thing, apparently, that no one really finds it rude if you eat with your mouth open. I heard this from a Vietnamese person, but if I'm wrong... well, lesson learned.