It’s a fun time to be a baseball fan right now: next week is the All-Star game, and soon after we’ll hit the trade deadline. In case you missed it, click here to see my trade deadline preview, and my view on the American League side of things. Today, we’ll take a look at the National League.

Washington Nationals

Poor, poor Nationals players. I’d say “Poor Nationals fans”, but they haven’t been around quite long enough for that suffering to really be tangible (ask a Cubs fan, then come back to me). The worst part of all, really, is that they’ve assembled a nice collection of young talent there, but it’s been fairly mismatched: too many outfielders, clashing personalities, and so on. Now that former GM Jim Bowden is out the door, hopefully the franchise can start turning itself around. The trade deadline would be a great start for this.

It’s worth noting that the Nationals already put together a significant trade, sending former top prospect turned problem player (turned AAA player) Lastings Milledge to the Pirates for Nyjer Morgan. Just about everyone sees this as a win for the Pirates: Morgan is 29, and is more or less a Juan Pierre type player who doesn’t hit for much power, but steals tons of bases (though he at least has an OBP around .350). Milledge, while he’s had trouble with teammates in the past, is still only 24 and can develop into a very good player.

In a way though, this trade is a microcosm of the direction the Nationals may be going in moving forward. For example, the Tampa Bay Rays traded two troubled, but high ceiling and talented players prior to going on their World Series run: Elijah Dukes (to the Nationals) and Delmon Young (to the Twins). In both cases, the team was giving up a big first round talent whose attitude didn’t mesh with the rest of the clubhouse. The Nationals may be looking to follow suit a bit here, first by creating a positive clubhouse, then building with talent from there.

Who they should be trading: When the Nationals signed Adam Dunn this past winter, it seemed strange. Why invest $20 million into a player when you’ll come in last place with or without him? And yet, in retrospect, this move looks brilliant. The Mets and Red Sox are among the teams who would love to have Dunn hitting cleanup for them, and the Nationals are asking for a high price in prospects. Essentially, the Nationals picked up Dunn as a short term investment to buy some quality prospects down the line. If he doesn’t go at the deadline, I expect he will be moved in the winter.

The Nationals have more or less made it clear that nearly anyone is available in a trade, especially younger veteran types like Austin Kearns, Nick Johnson and Josh Willingham. I expect all three of these guys to get traded, as the team hits a heavy “reset” button this year, and looks to a Strasburg future starting next year.

Pittsburgh Pirates

What’s happened to the baseball fans in Pittsburgh for a generation is absolutely unacceptable. They’re headed towards their 17th losing season in a row, which means that if you’re say, in your early 20s or younger, the Pirates have never been relevant. Not since 1992, to be specific.

However, there’s good news coming. For the first time in who knows how long, the team has a plan. The aforementioned Nyjer Morgan trade brought in Lastings Milledge, and Nate McClouth was traded for three of Atlanta’s best prospects. This leads to…

Who they should be trading: Everyone, and the Pirates, to their credit, are more willing to unload their veterans than any other team at the deadline this season. Jack Wilson, Matt Capps and Adam LaRoche have led the trade rumor mill, and you have to think they’ll listen in on pretty much any offer for their older players. At the end of the day, this team is looking to be built in the mold of Andrew McCutchen, Pedro Alvarez, and whatever young talent they can pick up during this transition (like Milledge). It may take a few years, but luckily they play in the NL Central, and it doesn’t hurt to have one of the most beautiful parks in the league. And hey, maybe one of those Indian cricket bowlers will become a steady pitcher.

San Diego Padres

I’ve already talked at length about potential Jake Peavy trades, and these days it’s looking like Padres management wishes Jake would have accepted the White Sox offer. He went down with an injury on June 13th, and who knows if he’ll be able to pitch and show he’s healthy before the deadline comes. Whether the trade comes now or in the winter, unloading the contract is essential for freeing up money to allow the Padres to put together a new, younger team.

It sounds like the team is looking into trading Adrian Gonzalez as well, but that isn’t likely to happen until the winter. Between these two moves, the team will get back enough prospects to refresh a fairly starved farm system. Part of the issue with their farm system in recent years has been a hesitance to draft players in the first few picks and pay out the money necessary for that talent (see the notorious Matt Bush pick), but this also looks to be changing course with the Donovan Tate pick a few weeks back.

Who they should be trading: Beyond Peavy and Gonzalez there aren’t many big names to trade, but teams will be interested. Scott Hairston was the only player on the team besides Gonzalez hitting consistently well in 2009, and he was just traded to the A’s for pitching prospects. I expect David Eckstein will follow suit, playing second, shortstop or a bench role for a contender. I could see Heath Bell being traded as well, but there’s something to be said for having a solid closer keeping morale high on a developing team: you at least win the games where you have a lead. But if there’s a team out there with a big need for a closer, I expect the Padres will make a deal. I’m sure they’d love to unload Brian Giles, but his production has been remarkably bad this year, plus he’s got a nearly $10 million contract on the books for 2009. No one will want any part of that.

Arizona Diamondbacks

Strategically, over the last few years, the Diamondbacks have been the polar opposite of the Padres. While San Diego has avoided big draft picks, Arizona has looked to get high ceiling, young players, watch them develop, and let the chips fall where they may. If nothing else, this makes things exciting: sometimes, you get a player with monster talent like Justin Upton. Other times, you get a Steven Drew, who seemed to finally be putting it all together last year, but has had some struggles this year. And sometimes you get a Chris Young, a guy with all the talent in the world who has a few massive holes in his game, and you wonder if he’ll ever patch them up and become a complete player.

Who they should be trading: This makes management decisions extremely difficult for the Diamondbacks, and I don’t envy their position. You don’t want to be the guy who traded Chris Young right before he learned to take a walk, and became a superstar. But you also don’t want to hold onto him one season too long, before his potential dissipates and you can’t get anything for him in a trade. The “Snakes” have already been bitten by this once, sending slugging Carlos Quintin to the White Sox, where he’s become a terrific hitter: when he’s not injured, anyway.

In any case, it’s clear that the fortunes of this Diamondbacks team rise and fall with the development of their young players, so it’s incredibly tough to figure out who to trade, if anyone. Any team with a 2010 including Brandon Webb, Dan Haren and Max Scherzer in the rotation has a bright future, so no massive overhaul is needed. I expect they’ll trade useful players whose contracts expire this year, like Doug Davis, Jon Garland, Chad Tracy, Felipe Lopez, and so on. Free up some money and roster spots for next year, pick up a reliable bat or two, get back a healthy Brandon Webb, and Arizona can contend again.

So there’s your trade deadline preview for the National League. Again, I don’t expect a ton of movement with big ticket players this season due to the economy, but these teams that have fallen out of contention can still use some creativity to rebuild for the future. And most importantly, the teams who do have star players (but are going nowhere otherwise) will hopefully be smart enough to make that big trade this year, to make future seasons better.